Frontline Test System

Transcription

1 Frontline Test System SerialBERT Async for Windows 9x/NT Manual Technical Support Frontline Test Equipment, Inc. PO Box 7507 Charlottesville, VA USA Voice: (804) Fax: (804) Web: FTP: ftp.fte.com Frontline is located in the Eastern time zone of the USA, usually five hours behind London, England. 1

2 Packing List * This Setup and Quick Start Guide * License Envelope with Product Registration Card and software System Requirements * PC with Windows 95 OSR2 (version 950b), Windows 98 or Windows NT loaded and a Pentium processor or higher * 16 MB of RAM (32 recommended for NT) * 5 MB free hard disk space * One serial port or internal modem * SerialBERT supports COM1 through COM64 * Maximum data rate supported is dependent on PC processor speed Copyright 2000 Frontline Test Equipment, Inc. All rights reserved. You may not reproduce, transmit, or store on magnetic media any part of this publication in any way without prior written authorization of Frontline Test Equipment, Inc. Frontline Test System is a trademark of Frontline Test Equipment, Inc. SerialBERT and Serialtest are registered trademarks of Frontline Test Equipment, Inc. All other trademarks and registered trademarks are property of their respective owners. 2

3 Table of Contents Introduction to Frontline Test System 6 Installing the Software...6 Starting SerialBERT...6 Choose your COM port...6 Quick Start Guide...7 Product Installation and Port Setup 9 Hardware Settings...9 Choosing Product and Com Port...9 Serial Port Info button...9 Installing and Uninstalling Products...9 Changing Icon Names...10 Moving Add-on Products...10 Control Window 11 Control Window Toolbar...11 Minimizing Windows...12 Test Setup 13 Test Setup Window...13 Test Length...13 Phone Number...14 Pattern and User Pattern...14 Block Size...14 Log File...14 I/O Configuration - Baud, Parity, etc. 15 Set I/O Configuration Window...15 Operating Mode...16 Setting Baud, Parity, Word Length and Stop Bits...16 Defining Your Own Baud...16 High Speed Baud Rates...16 Flow Control...16 Names...16 Bit Order...17 Duplex...17 Opening and Saving Configurations...17 Saving A Configuration to File...17 Opening a Saved Configuration...18 Running a Test 19 How to Start and Stop a Test...19 Manual and Automatic Error Insertion...19 Statistics Window 20 Reading the Statistics Window...20 The Statistics Toolbar...22 Viewing Control Signal Changes 23 Breakout Box Window

4 Reading the Breakout Box Window...23 The Breakout Box Toolbar...23 Breakout Box Options...24 Modem Operations 25 Sending Commands to a Modem...25 Modem Progress Window...25 Terminal...26 Modem Command Settings...26 Advanced Modem Settings...27 Loading and Saving Modem Configurations...28 Modem Strings Sent For Each Command...29 Reviewing Data 31 Review Events...31 List of All Event Symbols...31 Obtaining Information on Events...31 Switching Character or Number Sets...32 Mixed Sides...32 Font Size...32 Event Numbering...33 Saving Your Data...33 Saving the Entire Capture Buffer...33 Saving a Portion of a Capture File or Buffer...33 Searching...34 Searching for Errors...34 Control Signal Searching...35 Search by Pattern...37 Searching By Time...38 Go To Event...39 Side Restriction...39 Live Events...40 The Live Events Toolbar...41 Capture Options...41 Reviewing Control Signals 43 Signal Display Window...43 Reading the Signal Display...43 The Signal Display Toolbar...44 Signal Display Options...45 Printing 46 Review Events Printing...46 Print Preview...46 Troubleshooting Printing Problems...46 Export 47 Export Fields...47 Export Filter Out...48 Export Templates...48 Other Export Options...48 Export Header File...49 Exporting Baudot

5 Options 49 Line Grade Options...49 Thresholds...50 Control Signal Options...51 Transmit Options...51 System Settings...52 Common Options...52 Advanced System Options...52 Technical Information 54 Contacting Technical Support...54 The FTS Driver...54 Windows 95/98 Driver...54 Windows NT Driver...55 Windows 2000 Driver...56 Performance Notes...56 Note Concerning Ring Indicator...57 Handy Character and Other Tables...58 ASCII Codes...58 EBCDIC Codes...58 Communication Control Characters...58 Baudot Codes...60 FIFOs and FTS...60 Unprocessed Events...61 Disabling Control Signal Interrupts...62 Bit/Block Error Rate Testing Overview 63 Glossary 64 DTE Device...64 DCE Device...64 DTR - Data Terminal Ready...64 RTS - Request to Send...64 CTS - Clear to Send...64 DSR - Data Set Ready...64 CD - Carrier Detect...65 RI - Ring Indicator...65 RS Event...65 UART...65 Buffer Wrapping...65 Snapshot...65 Frame Recognizer...66 MIL-STD-188C...66 Overrun Error...66 Underrun Error...66 FIFO buffers...66 BERT Sync...66 USART

6 Introduction to Frontline Test System Welcome to the Frontline Test System! Frontline Test System (FTS) is a family of products designed to let you conduct data analysis using your personal computer. The FTS interface is easy to use without training, but you will want to read the manual to learn how to take maximum advantage of all the features. We have tried to make the manual complete and easy to use. The Table of Contents will guide you towards general information on different areas of the product, and the Index will help you find specific information on a particular topic. This entire manual is available in the online Help. Choose Help from the Help menu on the Control window or press F1 on any window to access Help. If you want to get up and running quickly, please read the Quick Start Guide which contains an overview of running a BERT test. Installing the Software If you are installing the product for the first time, follow these steps: Insert the media into the drive. Run SETUP.EXE. You can do this from the command line, Windows Explorer, or the Add/Remove Programs icon in the Control Panel. Follow the instructions on your screen. You will need your serial number (found on the registration card) to complete the installation. Fill out your registration card and send it in! This will help us to keep you informed on product upgrades. You can register online at our web site, If you are installing additional copies of FTS, follow these steps: Double-click on the Frontline Test System folder on your desktop, and double-click on the FTS Setup icon, OR Click on the Start button, and choose Programs > Frontline Test System > FTS Setup. Click on the Setup Tab and then click on the Install button. Enter your serial number. Click OK. Starting SerialBERT When SerialBERT is installed, it creates a folder called Frontline Test System on the desktop. This folder contains icons used to start SerialBERT, including icons for the help files, FTS Setup, and for the demos of each product. The icon for SerialBERT is called SB Async. If you have more than one copy of SerialBERT installed, the additional copies will have numbers following the icon name. To run SerialBERT, double-click on the SB Async icon. Choose your COM port 6

7 The Hardware Settings window appears when SerialBERT is started for the first time. Choose which port SerialBERT should use to transmit and receive data from the Serial Ports box. Click on the down arrow to show a list of all the serial ports available on your PC. There are six radio buttons at the top of the window. The first three refer to Serialtest Async and Serialtest Spy, which are asynchronous protocol analysis tools, and the last two refer to a version of Serialtest designed for use with a Modem Line Tap device. Select SerialBERT. Click OK when you are finished. If you need to change the serial port later, select Hardware Settings from the File menu on the Control window. Quick Start Guide The purpose of the Quick Start Guide is to help you get up and running with a minimum of work. The Quick Start includes an explanation of BERT testing and an overview of FTS. How to Use FTS The Control Window FTS is organized around the Control window. From the Control window you have access to the other windows used to manage various aspects of the program. In addition, test and modem functions are controlled from the Control window. To learn more about what each button does, read the help topic on the Control Window Toolbar. Modem Setup If you are using modems in your test, you will need to set them up with the correct parameters before starting the test. FTS provides command buttons for several common modem commands as well as a Terminal window for communicating with the modem directly. The commands can be changed in Modem Settings, which is accessed from the Modem menu. Dial dials the phone number entered in the Phone Number box on the Test Setup window Disconnect hangs up the phone Remote Loopback sends the command to enter remote loopback Local Loopback sends the command to enter local loopback Terminate Loopback sends the command to terminate loopback mode Auto Answer sends the command to automatically answer the phone No Auto Answer turns off auto answer mode Terminal opens the terminal window for communicating directly with the modem Setting Test Parameters There are two types of parameters to set; circuit parameters and test parameters. Circuit parameters are changed in the Set I/O Configuration window and include the baud rate, word length, parity, and number of stop bits. Click on the Set I/O button to open the Set I/O Configuration window. 7

8 Test parameters are changed in the Test Setup window. Click the Test Setup button to open the Test Setup window. Test parameters include the bit pattern, block size and the test length. If you are testing with modems and need to dial a phone number, you can enter the number to dial in the Phone Number box. (This is the number used by the Dial command when it dials the phone.) FTS has the ability to automatically insert bit errors at regular intervals. In the Automatic Error Insertion box, choose the desired units and the number of units. To log the results of a test to a text file, click on the Start Logging button and choose a filename. Then choose how often FTS should log. FTS can log at regular intervals, or only when errors occur. Log files are essentially snapshots of the Statistics window. They have.blg extensions and are comma-delimited text files that can be imported into spreadsheets or database programs. To close a log file, either click the Stop Logging button or close FTS. Running a Test Starting and stopping a test can be done from the Control, Test Setup or Statistics windows. Once a test is started, bit errors can be manually inserted using the error buttons. Start Test begins a new BERT test Stop Test ends a BERT test Insert 1 Bit Error inserts one bit error (inverts the value of one bit) Insert Error Burst inserts a burst of errors (inverts the value of every bit in one byte) Viewing Test Results The Statistics window is the main tool for analyzing test results. Click the Statistics button to open the Statistics window. This window has information on the number of bits, blocks and seconds sent and received, and the number with errors. It also includes information on the types of errors received (parity, framing, overrun, underrun, and buffer overflow), the effective data rate, and the elapsed test time. BERT Status and Line Grade give an indication of how the test is going. BERT Status refers to the current state of the test (No Data Received, Out of Lock or In Lock) while the Line Grade indicates the overall quality of the line. The Line Grade and Status are also displayed on the Control window status line, allowing you to run a BERT test with no windows other than the Control window open and still monitor the overall state of the test. The Line Grade and several of the statistics on the Statistics window are thresholds that can be changed from the Options window. Choose Options from the File menu to change the threshold values. Exiting FTS To exit FTS, go to the File menu on the Control window, and choose Exit. 8

9 Product Installation and Port Setup Hardware Settings The Hardware Settings box is used to tell FTS which product you want to use and which COM ports to use. This box will appear the first time you start the program. If you need to change your COM ports, you can do so at any time by choosing Hardware Settings from the File menu in the Control Window. Choosing Product and Com Port Choose Product There are six radio buttons at the top of the Hardware Settings window. These are: "Use FTS Cables", "Spy", "Source DTE, No Cables", "SerialBERT", "MLT, length 7 bits" and "MLT, length 8 bits". If you own SerialBERT, the SerialBERT button will be active. The other buttons refer to different versions of Serialtest, and will be active if you also own Serialtest. Otherwise they will be grayed out. Click on the SerialBERT radio button if it is not already selected. Choose COM port To change your COM port, click on the down arrow in the port box and choose one of the COM ports listed. This list is generated from the registry of your computer, and will only list the COM ports that are available on your computer. Changes in your COM port settings will take effect when you click on the OK button, or the next time you start FTS if you changed them from outside the program. Options Disable control signal interrupts - When checked, FTS will ignore all interrupts generated by the control signals. This is mostly a troubleshooting tool used when monitoring a circuit which has large numbers of rapid signal changes. Info button Provides information on whether the selected serial port has FIFO buffers and if they are enabled. Serial Port Info button Click the Info button on the Hardware Settings window to get information on the status of the FIFO buffers for the selected ports. FTS will provide information on whether the selected ports have FIFO buffers, and if they do, whether the buffers are enabled. This information is useful in FTS for troubleshooting performance problems. See FIFOs and FTS for more information. Installing and Uninstalling Products If you already have an FTS product installed, you can install additional products or uninstall a product from the FTS Setup window. 1. Double-click on the FTS Setup icon from the Frontline Test System folder on your desktop, or click on the Start button and choose Programs --> Frontline Test System --> FTS Setup. 2. Click on the tab labeled Setup. This tab shows you the serial numbers and name of every installed FTS product. 9

10 3. To install a new product, click on the Install button, and type in the serial number of the new product. 4. To remove a product, click on the product you want to uninstall, and then click the Uninstall button. Changing Icon Names 1. Double-click on the FTS Setup icon from the Frontline Test System folder on your desktop, or click on the Start button and choose Programs --> Frontline Test System --> FTS Setup. 2. Click on the Setup tab. 3. Click the product whose name you want to change. 4. Click the Modify button at the bottom of the window. 5. Type in the new name for the product. 6. Click OK. The name of the product tab in the FTS Setup window will change, as will the name of the icon used to start the product. To modify the name of an add-on product, select the name of the product the add-on is attached to. Moving Add-on Products Add-on products add functionality to stand-alone products. When add-ons are installed, they are attached to a stand-alone product. You can change which stand-alone product the add-on is attached to. 1. Double-click on the FTS Setup icon from the Frontline Test System folder on your desktop, or click on the Start button and choose Programs --> Frontline Test System --> Setup. 2. Click on the Setup tab. 3. Click the add-on you want to move. 4. Click the Modify button at the bottom of the window. 5. Select the product you want the add-on to attach to. 6. Click OK. 10

11 Control Window FTS is organized around the Control window (see image below.) The Control window toolbar buttons handle running a BERT test, sending modem commands and accessing other parts of the program. Hold the cursor over each button, and a ToolTip will pop up with its name. Because the Control window is so frequently used and because it has a tendency to get lost behind other windows, every window has a Home button that brings the Control window back to the front. Just click on the Home button to restore the Control window. The bottom status bar of the Control window gives a quick look at what is currently going on. The first item shows the state of the test with a color-coded LED and short description. Test states are Running, Not Active, and Flow Control Active. Not Active means that FTS is not currently running a test, Flow Control Active means that the test is running and flow control is active, and Running means that FTS is actively running a test. The next item on the status bar gives the current utilization on the circuit for both DTE and DCE, followed by the Line Grade. The Line Grade provides a quick reading of the overall quality of transmission over the communications link. There are four Line Grades ranging from Excellent to Unacceptable, and each has a color-coded LED associated with it. Line Grade will display Low Sample until enough data has been collected to make a meaningful determination. The last item is the Test Status. Test Status shows whether the test is In Lock or Out of Lock. Other statuses are No Data Received and End of Test. Control Window Toolbar Available options will be in color, while unavailable options will be grayed out. All toolbar buttons have corresponding menu items, most of which can be found in the Window menu. Set I/O Configuration - Use this window to tell FTS the characteristics of the circuit you are testing. Characteristics include baud, word length, parity, and stop bits. Test Setup - Use this window to tell FTS the characteristics of the test you want to run. This includes the bit pattern to use, length of test, automatic error insertion and whether to log test results to file. Start Test - Starts a BERT test. Send 1 Bit Error - Transmits a bit error by inverting a bit in the outgoing data stream. 11

12 Send Error Burst - Transmits a burst of errors by inverting all the bits in one word in the outgoing data stream. Stop Test - Stops the BERT test. Dial - Sends the modem command to dial the phone, followed by the phone number entered in the Phone Number field on the Test Setup window. Disconnect - Sends the modem command to disconnect from the circuit (hang up the phone.) Remote Loopback - Sends the modem command to enter remote loopback. Local Loopback - Sends the modem command to enter local loopback. Terminate Loopback - Sends the modem command to terminate loopback. Auto Answer - Sends the modem command to automatically answer incoming calls. No Auto Answer - Sends the modem command not to answer incoming calls automatically. Terminal - Opens the Terminal window used to communicate with the modem. Statistics - Tracks useful statistics such as bits sent and received, number and type of errors, and effective data rate. Statistics are kept for the duration of a test and for a subset of the test. Breakout Box - Functions as a passive breakout box, showing control signal changes for RTS, CTS, DTR, DSR, CD and RI in real-time. Signal Display - Shows the state of the control signals over time, beginning with the first event in the buffer or file. You can zoom in to view control signal states for just one event, or zoom out to view changes for the entire buffer. Cascade - Cascades all windows, with the first window being placed directly below the Control window. Minimizing Windows You can choose to minimize windows individually, or have all windows minimize when the Control window is minimized. To minimize all windows when the Control window is minimized, go to the Window menu in the Control window, and choose Minimize Control Minimizes All. When this is checked, minimizing the Control window will minimize all windows. When this is unchecked, all windows, including the Control window, can be minimized separately. Windows minimize to the top of the Task Bar. 12

13 Test Setup Test Setup Window The Test Setup window is used to set the parameters for a test. Options include the test length, pattern to be transmitted, block size and phone number. You can also specify a user pattern and open a log file to log a snapshot of the Statistics window to file at regular intervals. Test Length The Test Length parameter controls how long the receive test will run. Note that this parameter does not control how long FTS sends data, just how long it will receive data. The radio buttons determine if the test will run continuously or for a fixed length of time or data units. Click the Continuous button to have the BERT test run without stopping. Click Fixed Length to run the test for a specific length of time or specific number of bits/blocks. When the Fixed Length button is checked, you will be able to specify the length of the test. You can have a test run for a certain number of Bits, Blocks, Hours, Minutes or Seconds. Click on the arrow to choose a unit from the drop down list. To change the number of units, place the cursor in the box and type a number. 13

14 Phone Number This field is used in conjunction with the Dial button to command a modem to dial a phone number. Enter the number you want the modem to dial in this field. You can also enter other commands needed to dial the phone and they will be sent as part of the string. For example, you need to dial 9 to access an outside line, a comma to pause for the central office dial tone, followed by the number Enter 9, in the Phone Number box. Then click the Dial button to initiate the dialing sequence. Pattern and User Pattern The Pattern field controls the test pattern. All of the industry standard patterns are available. Other patterns are Alternating ones and zeroes, Mark (all ones) or Space (all zeroes.) You can also specify your own pattern by choosing User. Enter your pattern in the User Pattern box, and specify which character code to use (ASCII or EBCDIC). You can enter a string of characters, hex or binary values. Previously used User Patterns are saved in the history list. Click on the triangle to the right of the User Pattern box to view the history list and select an item from it. Patterns are saved to the history list only when they have been used to run a test. Entering Characters Place the cursor in the pattern box and type in your string. You can enter any character from a character set, with the following exceptions: \$&^. These characters are used as prefixes to let you to enter hex, binary, or control characters. The escape character is the backslash \. Use this character when you want to transmit one of the restricted characters. For example, to transmit a $, you would enter \$. To transmit a \, enter \\. Entering Hex or Binary To enter a hex value, enter a $ followed by two hex digits. For example, to enter hex 00 01, enter $00$01. If you need to specify the $ as a character, you can use \$. Just as the $ symbol tells FTS that the following characters are hex digits, the & symbol tells FTS that a binary number comes next. For example, to transmit binary , you would use & If you need to specify the & as a character, you can use \&. Entering Control Characters The ^ (caret) is used to enter the control characters Ctrl-A through Ctrl-Z and Ctrl-@,[,\,],- when using the ASCII character set. For example, ^A specifies Ctrl-A ($01) and ^@ specifies ASCII NUL ($00). If you need to specify the ^ as a character, you can use \^. Block Size The Block Size field may be either 1,000 (1k) bits, 10,000 (10k) bits, 100,000 (100k) bits, 100,000,000 (100M) bits or Pattern. If you select Pattern, and the Pattern field is set for Alternating 1/0, Mark or Space, then the block size is defined at 1,000 bits. Log File Logging is started from the Test Setup window. Click on the Test Setup icon in the Control window toolbar to open the Test Setup window. The logging functions are at the bottom of the window. 14

15 The log file is a text file designed to be imported into a spreadsheet, word processor or database. FTS logs by taking a snapshot of the data in the Statistics window. Field names are output once at the top of the file, followed by a snapshot on each subsequent line. Each snapshot is numbered sequentially beginning with the start of each test. The data fields are comma delimited and each line ends in a carriage return/line feed. Once opened, the log remains open until the Stop Logging button is clicked, or FTS is closed. The results for each test will be appended to the end of the log file, providing a record of multiple tests in one file. If you want a separate log file for every test, you will need to stop the current log and start a new log between each test. How to Log Click the Start Logging button to open a new log file. Enter a name in the file name box, specify what directory to store the log in, and click Open. By default the log file is opened in the Data directory. When a log is open, the Log File field changes from Inactive to the name of the file, and the Start Logging button changes to Stop Logging. FTS will log multiple tests to the same file; there is no need to open a separate log for each test. Choose how often to log. In the Log Every section, type how often FTS should log in the first field and choose the units in the second field. FTS will log based on Bits, Blocks, Seconds, Minutes, Hours, Bit Pattern Errors, or at the End of Test. If you want log entries based on the amount of data received, choose Bits or Blocks. If you want log entries based on the amount of time the test has been running, choose Seconds, Minutes or Hours. If you are only concerned with errors, choose Bit Pattern Errors (note that this only logs when bit pattern errors are detected, and not other types of errors such as parity.) Choose End of Test to log the final results of a test. With options other than End of Test, FTS will log at the desired intervals and will also log at the end of the test automatically. System performance may be affected if the frequency of logging is too high. We recommend choosing an interval that results in a log entry no more than once per second. For example, if the data rate is 9600 bits per second, choose to log every 9600 Bits, or choose a number larger than You can also log whenever a Line Grade change occurs in the Line Grade Options. Click Stop Logging to close the Log file. FTS will automatically close the log file if the file is still open when FTS is exited. I/O Configuration - Baud, Parity, etc. Set I/O Configuration Window The Set I/O Configuration window allows you to configure operating mode, baud, parity, word length and stop bits. If a configuration file is open, it will be listed at the top of the Set I/O Configuration window. If no configuration file is being used, FTS will revert to its default settings. You can revert to the factory default settings at any time by clicking on the Revert to Factory Defaults button toolbar. on the Set I/O Configuration 15

16 Operating Mode FTS has three operating modes: Send and Receive, Send Only, and Receive Only. In Send and Receive mode, FTS will both send data and receive it. Send Only mode means that FTS will send data during a test but will not receive it. In Receive Only mode, FTS will receive data, but will not send it. FTS operates in Send and Receive mode by default. Setting Baud, Parity, Word Length and Stop Bits To change the baud, parity, word length or number of stop bits, click on the down arrow next to the setting box and choose an option from the list. For baud, you can either choose a listed rate or enter a rate. Defining Your Own Baud To define your own rate, highlight the text in the baud field and type in a new rate. Not all baud rates are supported. Supported rates vary depending on the rates supported by the serial port. If you choose a baud that is not supported, FTS will display a box asking you to choose between the two nearest supported rates. You must choose a rate in order to continue working. High Speed Baud Rates Monitoring at speeds greater than 115.2Kbps requires AsyncExpress, a high speed version of Serialtest. Flow Control There are four flow control options: None, RTS/CTS, DTR/DSR or Xon/Xoff. The default option is None. Flow Control is typically set to None. Other selections are used when working with devices such as statistical multiplexers or in half duplex and multidrop applications. Hardware flow control can be accomplished using either the RTS /CTS pair or DTR /DSR pair. Choose which pair you would like FTS to use. To use software flow control, choose the Xon/Xoff option. FTS will use the Xon/Xoff characters given in the boxes below the flow control option. These numbers must be specified in hexadecimal (hex) characters. By default, FTS uses hex 11 for Xon and hex 13 for Xoff. Note that Software Flow Control should not be used with pseudo-random bit patterns such as 63, 511, etc. Names Following is a list of all the labels used in FTS to identify errors, control signals, and DTE/DCE devices. To change the labels, click the Names button on the Set I/O Configuration window. Changes to the labels will be used throughout the program. For example, changes to the control signal labels will be used in the Breakout Box window. Sides The Sides section allows you to give your DTE and DCE devices more descriptive names. Errors FTS recognizes three types of errors: Overrun, Parity and Framing. This section allows you to change the error labels. Signals Labels for the six control signals monitored by FTS are given below. Label Control Signal 16

17 RTS CTS DSR DTR CD RI Request to Send Clear to Send Data Set Ready Data Terminal Ready Carrier Detect Ring Indicator If you are used to different abbreviations for the same signals, you can change them in this section. For example, if you normally refer to Carrier Detect as DCD, highlight CD and type in DCD. Bit Order Choose LSB (least significant bit) first or MSB (most significant bit) first. LSB first is normal, while MSB first is considered "reversed" from normal. This option reverses the order of the bits within each byte. All options on the Set I/O window are valid when in MSB mode except for parity. The parity must be None when using MSB bit order. Duplex FTS can transmit data in either full or half duplex mode. At present only the full duplex mode is available. A full duplex test can be run with one BERT tester and a loopback at the remote end. Half Duplex is used to transmit data in only one direction at a time over the data link even though the data link may be capable of full duplex operation. Half duplex testing requires a BERT tester at each end of the link; in Half duplex mode, FTS does not transmit data while it is receiving data. Half duplex operation with a Flow Control of None will produce a "ping-pong" test. This test ignores control signals and is usually used on a full duplex communications link. When a "ping-pong" test is started, FTS waits for a block from the other tester. If a block is not received within Sync Loss Timeout Seconds, FTS will transmit a block, causing the "ping-ponging" to begin. As soon as a complete block is received, FTS begins transmitting. Normally half-duplex operation should be run with Hardware Flow Control selected. The RTS/CTS control signals are used to control the direction of transmission and to signal when the line has "turned around." Opening and Saving Configurations Saving A Configuration to File Configuration files include all the information on the Set I/O Configuration window as well as the settings on the Test Setup window. They also store the settings on the BERT Options window. 1. Set up your configuration on the Set I/O Configuration and Test Setup windows. 2. If a configuration is already open and you have altered it, go to the File menu and choose Save As; otherwise, click on the Save Configuration button. 3. In the File name box, type a name for your configuration. You do not need to add an extension. FTS will add a.brt extension automatically. 4. By default, FTS will save the configuration in your Data directory. Choose a different directory to save the configuration elsewhere. 5. Click on Save. If you make a new configuration and do not save it, FTS will ask you if you want to save your configuration when you exit the program. If you want to save your configuration, choose Save and the Save File dialog box will appear. If you do not want to save your configuration, choose Cancel. 17

18 Opening a Saved Configuration Configurations are saved with a.brt extension, and are located in your Data directory by default. Configuration files include the settings in both the Set I/O Configuration window and the Test Setup window. 1. Click on the Open Configuration button. If other configurations have been used recently, a menu listing the last four configurations used will be displayed. 2. Select a recent configuration file, or choose Open to load an unlisted configuration. 3. If you have saved your configurations in the default directory, they will be listed in the window. Choose a different directory if your configurations are saved elsewhere. 4. Select the configuration you want to use, and click on Open. The name of the open configuration file is displayed at the top of the Set I/O Configuration and Test Setup windows. If no configuration file is open, Untitled will be displayed. 18

19 Running a Test How to Start and Stop a Test Use the four test buttons on the Control or Statistics windows to start and stop tests. The buttons on both windows are identical in function and are provided in both places for convenience. The buttons are also provided on the Test Setup window. Start Test - Starts a BERT test using the parameters provided in the Set I/O Configuration and Test Setup windows. Send 1 Bit Error - Transmits a bit error by inverting a bit in the outgoing data stream. Send Error Burst - Transmits a burst of errors by inverting all the bits in one word in the outgoing data stream. Stop Test - Stops the BERT test. Modem command functions are disabled while the test is running. Manual and Automatic Error Insertion You can insert errors into the data stream either manually or automatically. Click on the appropriate button in the Error Insertion section to insert one bit error or a burst of errors. FTS inserts one error by inverting one bit, while an error burst is inserted by inverting all the bits in one byte. (The length of a byte is defined in the Word Length field on the Set I/O Configuration window.) Both of these errors can be inserted at any time and as often as required. FTS can insert errors automatically at regular intervals. Select the type of units in the second field of Automatic Error Insertion, and then type the number of units in the first field. 19

20 Statistics Window The Statistics window supplies information about the circuit under test, and provides the basic functions necessary to start and stop a test. Statistics gathered include: bits, blocks and seconds sent and received, number of errors and error rate, Sync Lost Seconds and Occurrences, and Effective Data Rate. A summary of the line quality and timing information is shown at the top of the Test and Resetable tabs. The Test tab shows information gathered for each test. The Test information resets at the beginning of each test, but cannot be cleared during a test. The Resetable tab can be cleared during a test, in effect giving you information on a subset of the test data. Reading the Statistics Window Each item is described in order, from the top down and left to right. Test Results From: Displays the date and time the test was started. Elapsed Test Time: Amount of time that has elapsed since the test was started, displayed in HH:MM:SS:mmm, where H = Hours, M = Minutes, S = Seconds, and m = milliseconds. If a test runs for more than 24 hours, a counter for days is added to the front. Line Grade: An indicator of the quality of the line. The Line Grade can be Excellent (green), Good (blue), Poor (yellow), or Unacceptable (red). Low Sample is displayed when insufficient data has been received to make a determination of Line Grade. Line Grade is based on received time, not elapsed test time, and is updated once per minute. The thresholds for each grade can be changed in the Line Grade Options. Unprocessed Events: An indicator of the current number of events in the buffer that have not been processed and the maximum peak value of unprocessed events. Choose Show Unprocessed Events from the View menu to display this item on the Statistics window. Click here for more information on what this indicator means. BERT Status: The status of the test. Test statuses are No Data Received, In Lock, and Out of Lock. In Lock means that data is of high enough quality and is being received frequently enough to keep the test in sync. Out of Lock means that the test is not in sync. This is either because the Bit Error Rate has been greater than ¼ over the course of the last 1/18 of a second or no data at all has been received during the most recent second. (The ratio can be changed in the Thresholds Options.) Timestamp: The current date and time is shown in the top left corner of the grid. Sent Bits/Blocks/Seconds: The total number of bits and blocks sent and the number of seconds during which data has been sent. Received Bits/Blocks/Seconds: The total number of bits and blocks received and the number of seconds during which data has been received. These counters advance only when the test is In Lock. Error Bits/Blocks/Seconds: The total number of bits and blocks found in error. The error seconds counter is incremented when one or more errors occur in each one seconds interval. These counters advance only when the test is In Lock. Error Free Bits/Blocks/Seconds: The total number of bits and blocks which were error free. The error free seconds is the total number of seconds containing no errors during which data has been received. Error Rate: The percentage of error bits, blocks and seconds. The percentages are the number of Error Bits/Blocks/Seconds divided by the Received Bits/Blocks/Seconds. 20

21 Sync Lost Seconds: The total number of seconds that the test was out of sync. Sync Lost Occurrences: The total number of transitions from In Lock to Out of Lock during the test. Severe Error Seconds: The total number of seconds in which the Bit Error Rate is greater than 1/1000. (This value can be changed in the Thresholds Options.) Degraded Minutes: The number of one minute intervals during the test with a Bit Error Rate greater than 1/1,000,000. The one minute intervals are determined according to CCITT Recommendation G.821: "The 1 minute intervals are derived by removing unavailable time and severely errored seconds from the total time and then consecutively grouping the remaining seconds into blocks of 60." (This value can be changed in the Thresholds Options.) Available/Unavailable Seconds: The number of available and unavailable seconds during the test. According to CCITT Recommendation G.821: "A period of unavailable time begins when the Bit Error Ratio in each second is worse than 1/1,000 for a period of 10 consecutive seconds. These 10 seconds are considered to be unavailable time. The period of unavailable time terminates when the Bit Error Ratio in each second is better than 1/1,000 for a period of 10 consecutive seconds. These 10 seconds are considered to be available time." (This value can be changed in the Thresholds Options.) Parity/Framing Errors: The total number of framing and parity errors. Start, stop and parity bits are not included in the count of total number of bits sent and bits received. Framing and parity errors do not count as Bit Errors. UART/USART Overrun Errors: The total number of overrun errors. If overrun errors occur, it is highly unlikely that a meaningful test can be conducted without changing the test conditions. Underrun Errors: The total number of underrun errors. This field is valid only for synchronous BERT. Driver Buffer Overflows: The number of bytes lost due to buffer overflow. Buffer overflow occurs when data is coming in too fast for FTS to process it. See Performance Notes for more information. BERT Buffer Overflows: The number of bytes lost due to BERT buffer overflow. BERT buffer overflow occurs when data is coming in too fast for FTS to process it. If the overflow occurs only when the computer is also doing other things (such as opening another application), it may be possible to eliminate the overflow by increasing the size of the buffer. See the Performance Notes for more information. DTE/DCE baud: The baud rate listed in the Set I/O Configuration window. Average Data Rate Out: The average of the number of bits sent over time. FTS is not able to accurately measure the number of bits sent in each second because a serial device with large buffers or the use of flow control may cause data sent by FTS to be held in a buffer before being placed on the circuit. The average data rate out is therefore a more accurate measurement of throughput. Effective Data Rate In: The number of bits received each second. Transmitter: Indicates whether BERT is actively transmitting data. The status will be Inactive if BERT is in Receive Only mode, and will be Initializing until data is transmitted. Receiver: Indicates whether BERT is actively processing received data. The status will be Inactive if BERT is in Send Only mode, and will be Initializing until data is received. 21

22 The Statistics Toolbar Show Control Window - brings the control window to the front. Reset - resets the Resetable Statistics tab. Freeze - freezes the display. Click once to freeze the display, and click again to resume. Change Font Size - click to change the font size. Test Setup - brings up the Test Setup window, which controls test parameters. Start Test - starts a BERT test. Insert 1 Bit Error - inserts one bit error in the data stream (inverts the sense of one bit). Insert Error Burst - inserts an error burst in the data stream (inverts the sense of each bit in a whole byte). Stop Test - terminates the test. 22

23 Viewing Control Signal Changes Breakout Box Window The Breakout Box window provides a real-time graphical view of control signals. The window is customizable based on the control signals you wish to view and your preference of indicators (+/-, 1/0, T/F, arrows, and simulated LEDs). Also included are counters showing the number of times a control signal has changed. FTS monitors six RS-232 control signals. These are: DTE Signals DTR - Data Terminal Ready RTS - Request to Send DCE Signals CTS - Clear to Send DSR - Data Set Ready CD - Carrier Detect RI - Ring Indicator (see the special note on capturing Ring Indicator changes) To open this window Click the Breakout Box button on the Control window toolbar. Reading the Breakout Box Window The Breakout Box display is divided into three main parts. The first part (to the far left of the screen) shows the abbreviated name of the control signal being monitored. These names can be changed in the Set I/O Configuration screen by choosing Names. The second part shows the control signal counters. The counters show how many times each control signal has changed state. This is useful in situations when signals may be changing state too rapidly to be displayed graphically. The third part of the Breakout Box shows the current states of the control signals. The indicators show the state that the control signal is currently in, and the line graph displays the state of the signal over time. A single line means that the signal is logically off, while a double line means that the signal is logically on. A half-height "tick" means that a signal has gone through one full transition (from off to on to off, or vice versa) since FTS last updated the screen. To change the indicators or the rate at which FTS updates the window, click on the Options The Breakout Box Toolbar Home - brings the Control window to the front. Reset - resets the Breakout Box window. button. Freeze - freezes the display. Click once to freeze the display, and click again to resume. Options - Brings up the Breakout Box Options window. This window allows you to change the window refresh rate and choose which control signals to display. 23

24 Breakout Box Options Display Signal This box shows which control signals FTS monitors. A check mark next to a control signal name indicates that the breakout box will display the status of that control signal. To prevent FTS from displaying the status of a signal, uncheck the box next to it. Window Refresh Rate The refresh rate is the rate at which FTS updates the window. By default, FTS refreshes the display once every 1,000 milliseconds (one second.) To change the rate, highlight the number in the box and enter a new number. See Performance Notes for information on how Window Refresh Rate can affect performance. Indicators You can choose what type of indicators FTS will use. The default indicators are a green "+" sign to show a logically high state, and a red "-" sign to show a logically low state. To change the indicators, click on the down arrow and choose a pair of indicators from the list. As a reminder, FTS gives the definition of the indicators in the top part of the Breakout Box window. To open this window Click the Options button on the Breakout Box toolbar. 24

25 Modem Operations Sending Commands to a Modem FTS provides toolbar buttons for sending commonly used commands to a modem. The modem command buttons are active only when in asynchronous mode, and only when in Send Only (DTE), Receive Only (DCE) or Send DTE, Receive DCE modes. The buttons are not active in synchronous mode or when FTS is operating as a DCE device. Use the Terminal window if you need to send commands to a device when FTS is operating as a DCE device or if you need to send specific commands to a modem. To issue a command, click on the appropriate toolbar button. The Modem Progress window will appear and display the commands sent and the response from the modem. Dial - Sends the modem command to dial the phone, followed by the phone number entered in the Phone Number field on the Test Setup window. Disconnect - Sends the modem command to disconnect from the circuit (hang up the phone.) Remote Loopback - Sends the modem command to enter remote loopback. Local Loopback - Sends the modem command to enter local loopback. Terminate Loopback - Sends the modem command to terminate loopback. Auto Answer - Sends the modem command to automatically answer incoming calls. No Auto Answer - Sends the modem command not to answer incoming calls automatically. Each command actually consists of a series of commands. Click here for a list of which strings are sent for each command. You can change the default strings sent for each command in the Modem Settings window. Modem Progress Window The Modem Progress window is displayed whenever a modem command has been sent. It shows the status of the modem command at the bottom of the window and any responses received from the modem in the text box. You may not type commands to the modem from this window; use the Terminal window to communicate directly with the modem. Click OK to close the window if the command has been successful, or Retry to try the command again if not successful the first time. The command strings can be changed from the Modem Settings window. 25

26 Terminal The Terminal is designed to emulate a dumb terminal window, and let you send commands to your modem. The Terminal has a text box for entering commands and displays the state of the control signals to the right of the box. To send commands to the modem, place the cursor in the text window and type your command. Press Enter to send it. The response from the modem will be displayed on the screen. Note that the characters you type will only be displayed on the screen if the modem has been configured to echo any characters sent to it. Similarly, the modem's responses will only be displayed if the modem has been configured to return result codes. The state of the control signals is displayed to the right of the text window. Either the DTE or DCE signals will be active and can be changed, depending on the current mode. Note that FTS functions only as a DTE device, and so you will only be able to change the DTE control signals. A check next to a signal means that the signal is logically high. Changes to control signals made from the terminal window are active only as long as the terminal window is open. When the terminal window closes, the control signals will revert to the state they were in before the terminal was opened. See Control Signal Options for help on setting control signals while running a test. Check the Local Echo box to echo the characters typed into the terminal. Otherwise the terminal will not display the characters typed unless the modem is echoing characters back to the terminal Check the Display as 7 Bit ASCII box to change the display from 8 Bit ASCII to 7 Bit ASCII. Modem Command Settings The AT command language provides a means to initiate modem actions and to change modem configurations. FTS modem commands can be configured in the Modem Settings window to match the requirements of your modem. FTS often sends more than one command string to complete a modem command. Click here for a list of which strings are sent for each command. The default command strings used by FTS are for a US Robotics Courier modem. Your modem may use different commands, in which case you can change the command strings and save them in a modem configuration. Check your modem's users manual for the command strings used by your modem. Modem commands can only be used when in asynchronous mode. Modem command options will be grayed out when in bisynchronous or isochronous mode. Advanced Modem Settings (additional command strings) Loading and Saving Modem Configurations Modem Initialization FTS starts almost every command sequence to the modem with an ATZ so that the modem is in a known state. Additional commands can be added to this initialization sequence as required by your application. Dial Number The dial command has many options that can be entered before the telephone number. These options can be entered into the Dial string along with the telephone number on the Test Setup window or they can be entered into the Dial Number field which is sent before the telephone number on the Test Setup window. 26

27 The default string is ATDT where AT is the attention code and DT is the dial touch-tone command. FTS also sends the Disable Error Correction and Compression command before sending the Dial command. Auto Answer FTS sends ATS0=1 to tell the modem to automatically answer incoming calls. No Auto Answer FTS sends ATS0=0 to tell the modem not to answer incoming calls automatically. Modem Timeout Seconds Before sending the dialing command FTS sends the S7=n command where n is the number in the Modem Timeout Seconds field. If the modem doesn't sense carrier from the remote end within the time specified, it will send a No Carrier result code to FTS. Restore Modem Defaults FTS sends AT&F to restore the modem to factory default settings. Choose Set Modem Defaults Now from the Modem menu to send this command. Halt Test on Carrier Loss Halt on Carrier Loss will stop a test if Carrier Detect changes from on to off at any time during a test. Check the box to activate this feature. Advanced Modem Settings Disconnect FTS sends ATH0 to tell the modem to hang up the call. Display Result Codes FTS relies on receiving result codes from the modem in verbose form. At every initialization, it sends ATQ0V1 to command displaying of verbal response codes. Q0 is the command to send result codes, and V1 instructs the modem to send them in verbal rather than numeric form. Disable Error Correction and Compression; Enable Hardware Flow Control Three commands are combined in this field: disable error correction, disable compression, and enable hardware flow control. The combined command is AT&M0&K0&H1. &M0 disables error correction, &K0 disables compression, and &H1 enables hardware flow control. This command is sent before FTS dials a phone number. It is important to disable the modem's asynchronous error control capabilities to get a true measure of the error rate of the link. It is also important to disable data compression to ensure that the test pattern is transmitted unaltered. Enable Hardware Flow Control enables RTS/CTS flow control from the modem to the DTE device (usually the PC running FTS.) This command is present to ensure that when hardware flow control has been selected in the Set I/O window of FTS, both FTS and the modem use hardware flow control. Otherwise it is possible to have hardware flow control selected in FTS, run a test, and have the modem not use flow 27

28 control. When hardware flow control is not selected in the Set I/O window in FTS, this command has no effect on the test. Note: Many modems that do not have error control will still accept the &M0 command and ignore it since it doesn't apply. However, some modems will not operate properly when given this command. For those modems you can remove the &M0 command. Similarly modems that do not have compression capabilities will return an error when the &K0 is issued. Remove the &K0 command for these modems. Local Loopback FTS sends AT&T1 to command local loopback. FTS sends the Disable Error Correction and Compression command before sending the command for local loopback. Remote Loopback FTS sends AT&T6 to command remote digital loopback. The normal modem default is usually to ignore the remote digital loopback command. It may be necessary for someone at the remote site to instruct the remote modem to accept the remote digital loopback command by sending it the AT&T4 command. Terminate Loopback FTS sends AT&T0 to end the test. This command does not cause the modem to hang up so press the Disconnect button if you wish to hang up the call. Accept Remote Loopback FTS sends AT&T4 to command the modem to accept the remote loopback command from another modem. Choose Accept Remote Loopback from the Modem menu to send this command. Refuse Remote Loopback FTS sends AT&T5 to refuse the remote loopback command if is received from another modem. Choose Refuse Remote Loopback from the Modem menu to send this command. Escape Code Character The normal escape code character is +. This character is sent three times in a row. If your application sends three consecutive pluses you can change the escape code character to avoid accidentally entering the command mode. You must also set the matching escape character in the modem. Modem Guard Time (milliseconds) This is the amount of time that FTS will wait before and after sending the Escape Code sequence to the modem. The guard time is required so that the modem does not interpret the escape code sequence as data. Loading and Saving Modem Configurations Modem configurations save all the values on the Modem and Advanced Modem Settings windows, and have a.mdm extension by default. You can customize the modem strings for a particular modem and save those values as a configuration. To save a configuration, click on the Save As button on the Modem Settings window, and give your configuration a name. To save changes to an existing configuration, click Save after making your changes. To load an existing configuration, click Load and choose the configuration to load. 28

29 Modem Strings Sent For Each Command When FTS sends a modem command through a modem command button or menu item, usually several commands are sent. Below is a list of the commands sent for each button or menu item. FTS waits for the amount of time specified in the Modem Guard Time before and after sending the Escape Code sequence. This ensures that the Escape Code sequence is not interpreted as data. Dial Escape Code Initialization Display Result Codes Disable Error Correction and Compression; Enable Hardware Flow Control Modem Timeout Seconds Dial Phone, followed by number entered in the Phone Number box on the Test Setup window Disconnect Escape Code Display Result Codes Disconnect Remote Loopback Escape Code Display Result Codes Disable Error Correction and Compression; Enable Hardware Flow Control Remote Loopback Local Loopback Escape Code Initialization Display Result Codes Disable Error Correction and Compression; Enable Hardware Flow Control Local Loopback Terminate Loopback Escape Code Display Result Codes Terminate Loopback Accept Remote Loopback Escape Code Display Result Codes Accept Remote Loopback Refuse Remote Loopback Escape Code Display Result Codes Refuse Remote Loopback Auto Answer Escape Code Initialization Display Result Codes Auto Answer No Auto Answer Escape Code 29

30 Initialization Display Result Codes No Auto Answer Modem Defaults Escape Code Initialization Display Result Codes Reset to Modem Defaults 30

31 Reviewing Data Review Events The Review Events window is a data review screen that provides detailed information about every captured event. By default, FTS displays the events using hex for bytes and symbols for other events on the left side of the window, with the appropriate characters shown on the right. Data is displayed with DTE data appearing on a white background and DCE data appearing on a gray background. Labels are provided between the hex and character data to help differentiate between DTE and DCE data. In FTS, DTE (outgoing) data is not captured during a test, only during modem commands and when the Terminal window is open. DCE data is always captured. The window is laid out like a spreadsheet. On the left side are row labels and at the top are column labels. 16 events are shown in each row. The labels are always displayed in hex. Bytes with errors are shown in red, to make them easy to spot. List of All Event Symbols By default, FTS shows all events. If you want to view only the data bytes, click on the All Events button. Click again to view all events. In addition to data bytes, the events shown are (in alphabetical order): Abort Buffer Overflow Control Signal Change Flow Control Active Flow Control Inactive I/O Configuration Change Long Break Low Power (ComProbe only) Short Break Sync Dropped (ComProbe only) Sync Found (ComProbe only) Sync Lost (ComProbe only) Test Device Stopped Responding (ComProbe only) Test Device Began Responding (ComProbe only) Underrun Error (ComProbe only) Unknown Event Obtaining Information on Events You can obtain detailed information on individual events or groups of events from the Review Events and Live Events windows. Click on an event to display information about it in the 3 lines at the bottom of the screen. You can also highlight multiple events to obtain information such as CRC and data rate. 31

32 The first line always shows the event number and the total number of events in the file or buffer on the left, followed by the timestamp on the right (if available.) If you have selected multiple events, the first line gives the first and last event selected, and the timestamps of both the first and last event. See Event Numbering for more information on how FTS numbers events. The second line has labels for the information shown on the third line. The information on these lines varies with the type of event and whether you are looking at one event or multiple events. Information on a single byte includes the source (whether DTE or DCE), character and numerical values, the state of the control signals at the time the byte was captured, and any errors associated with the byte. Information on multiple events includes the data rate, the amount of time that elapsed between the first and last byte (referred to as delta), the CRC and the state of the control signals. A "Chg" in a control signal box indicates that the signal changed state somewhere in the selection. Switching Character or Number Sets Options for data display include: Number formats - hex, binary, octal and decimal Character sets - ASCII, 7 bit ASCII, EBCDIC and Baudot. By default, FTS will display data in hex and ASCII. To change the number or character set, go to the Data menu on the Control window and highlight your choice. A check mark next to a character or number set indicates which set is currently being used. In the Review and Live Events windows, you can also right click on the header labeled Hex, and choose a number format from the list. To change the character set, right click on the header labeled ASCII, and choose a character set from the list. If you want to see only the numerical values, click on the Numbers Only button. If you want to see only the characters, click on the Characters Only button numerical and character display.. Click on the button again to return to both Mixed Sides If you want to get more data on the screen, you can switch to mixed sides mode. This mode puts all the data together on the same line. DTE data is shown on a white background and DCE data is shown on a gray background. Click once on the Mixed Sides button DTE over DCE mode. to put the display in mixed sides mode. Click again to return to You can also right click on the DTE/DCE labels in the center of the data display window to change between mixed and DTE over DCE modes. Choose Display Sides Together to go to Mixed Sides Mode, and Display Sides Separately to go to DTE over DCE mode. Font Size 1. Click on the Font Size button. 2. Click on the down arrow to choose a font size from the list. 3. Click OK. You can also change the font size by positioning the mouse cursor over the grid lines on the left side of many windows. When the cursor is positioned properly, it will change to a double arrow. Click and drag down to increase the font size, or drag up to decrease the font size. 32

33 Event Numbering This section talks about how events are numbered when they are first captured and how this affects the display windows in FTS. The information in this section applies to frame numbering as well. When FTS captures an event, it gives the event a number. If the event is a data byte event, it receives a byte number in addition to an event number. There are usually more events than bytes, with the result is that a byte might be listed as Event 10 of 16 when viewing all events, and Byte 8 of 11 when viewing only the data bytes. The numbers assigned to events that are wrapped out of the buffer are not reassigned. In other words, when event number 1 is wrapped out of the buffer, event number 2 is not renumbered to event 1. This means that the first event in the buffer may be listed as event of 16334, because events have been wrapped out of the buffer. Since row numbers refer to the event numbers, they work the same way. In the above example, the first row would be listed as 2d00 (which is hex for ) The advantage of not renumbering events is that you can save a portion of a capture file, send it to a colleague, and tell your colleague to look at a particular event. Since the events are not renumbered, your colleague s file will use the same event numbers that your file does. Saving Your Data You can save all or part of a capture buffer displayed in the Review Events window. You can also load a previously saved capture file, and save a portion of that file to another file. This feature is useful if someone else needs to see only a portion of the data in your capture file. For example, you have a ten megabyte capture file and the home office needs to see only two megabytes of that file. You can save only the two megabytes they need to see in a new file. The Save button and Save menu item are grayed out while data is being captured. You must pause capture before saving. Saving the Entire Capture Buffer 1. On the Control window, click on the Pause button to pause data capture. You cannot save a buffer to file while data is being captured. 2. Open the Review Events window. 3. Click the Save button. 4. Click on the radio button labeled Entire buffer. 5. Type a filename in the Save As box at the bottom of the screen. When you are finished, choose OK. Saving a Portion of a Capture File or Buffer 1. On the Control window, click on the Pause button to pause data capture. You cannot save a buffer to file while data is being captured. 2. Open the Review Events window. 3. Select the portion of the data that you want to save. Click and drag to select data. You can also click on an event to place the cursor, scroll down to the end of the area you want to select, hold down the Shift key and click on the end event. 4. On the Review Events window, click the Save button. 5. Click on the radio button labeled Selection. (This should already be chosen by default.) Make sure the starting and ending event numbers are correct. 6. Enter a filename in the Save As box. 33

34 7. Choose OK. Searching FTS allows you to search your capture buffer or capture file by pattern, control signal, error, or timestamp. You can also move through the buffer a specified number of events at a time, or go to a specific event anywhere in the buffer. 1. Capture some data to the buffer, or open a capture file to search. 2. Open the Review Events window. 3. Click on the Find button or choose Find from the Data Menu. 4. The Find window has five tabs, one for each type of search. Click on a tab to do that type of search. Press F3 to repeat any search. Searching for Errors FTS can search for several types of data errors. You can choose which errors you want to search for, and you can choose whether to search just the DTE or DCE data, or both. Bytes with errors are shown in red in the Review Events window, making it easy to find errors visually when looking through the data. Selecting Which Errors to Search The section with the check boxes allows you to choose which errors FTS should look for. If you want to search only for overrun errors, you would check the overrun box, and uncheck the other boxes. To search for all types of errors, check all boxes. Click on a box to check or uncheck it. Searching for Error Conditions The first three options are all fairly similar, and are described together. These options are searching for an event where: one or more error conditions changed one or more error conditions occurred one or more error conditions were off (i.e. no errors occurred). The most common search is looking for a few scattered errors in otherwise clean data. To do this type of search, choose to search for an event where one or more error conditions occurred, and then choose which errors to look for. By default, FTS will look for all types of errors. In contrast, searching for an event where one or more error conditions were off means that FTS will look for an event where the error(s) were not present. For example, if you have data that is full of framing errors, and you know that somewhere in your 20 megabyte capture file the framing got straightened out, you could choose to search for an event where one or more error conditions were off, and choose to search only for framing. FTS would search the file, and find the point at which framing errors stopped occurring. Searching for an event where the error conditions changed means that FTS will search the data and stop at every point where the error condition changed from on to off, or off to on. For example, if you have data where sometimes the framing is wrong and sometimes right, you would choose to search framing errors where the error condition changed. This would first take you to the point 34

35 where the framing errors stopped occurring. When you click Find Next, FTS will stop at the point when the errors began occurring again. FTS takes the current selected byte as its initial condition when running searches that rely on finding events where error conditions changed. FTS will search until it finds an event where error conditions changed or it reaches the end of the buffer, at which point FTS will tell you that there are no more events found in the buffer. If you are searching for an exact match, FTS will ask you if you want to continue searching from the beginning of the buffer. Searching for Exact Error Conditions To search for an exact state means that FTS will find events that exactly match the error conditions that you specify. First choose to search for an event where your choices exactly describes the state. This will change the normal check boxes to a series of radio buttons labeled On, Off and Don t Care for each error. On means that the error occurred, Off means that the error did not occur, and Don t Care means that FTS will ignore that error condition. Select the appropriate state for each type of error. Example: If you need to find an event where just an overrun error occurred, but not any other type of error, you would choose overrun error to be On, and set all other errors to Off. This will cause FTS to look for an event where only an overrun error occurred. If you want to look for events where overrun errors occurred, and other errors may have also occurred but it really doesn t matter if they did or not, choose overrun to be On, and set the others to Don t Care. FTS will ignore any other type of error, and find events where overrun errors occurred. To find the next error, click the Find Next button. To find an error that occurred earlier in the buffer to where you are, click the Find Previous button. Control Signal Searching Control signal searching allows you to search for changes in control signal states for one or more control signals. You can also search for a specific state involving one or more control signals, with the option to ignore those control signals whose states you don t care about. FTS takes the current selected byte as its initial condition when running searches that rely on finding events where control signals changed. Selecting Control Signals to Search The section with the check boxes allows you to specify which control signals FTS should pay attention to when doing the search. FTS will pay attention to any control signal with a check mark. Click on a box to place a check mark next to a control signal, and click again to uncheck the box. By default, FTS will search all control signals, which means all boxes start out checked. For example, if you are only interested in finding changes in RTS and CTS, you would check those two boxes and uncheck all the other boxes. This will tell FTS to look only at the RTS and CTS lines when running the search. The other signals will be ignored. Searching for On, Off, or Changed States The first three options are all fairly similar, and are described together. These options are searching for an event where: 35

36 one or more control signals changed one or more control signals changed from off to on one or more control signals changed from on to off. Searching for an event where one or more signals changed means that FTS will look at every control signal that you checked, and see if any one of those signals changed state at any time. If you want to look at just one control signal, you would check the box for that signal and uncheck all the other boxes, and then choose to search for an event where one or more signals changed. FTS will note the state of the selected signal at the point in the buffer where the cursor is, search the buffer, and stop when it finds an event where RTS changed state. If the end of the buffer is reached before an event is found, FTS will tell you that no matches were found. Searching for events where control signals changed state from off to on, or vice versa, is most useful if the signals are usually in one state, and you want to search for occasions where they changed state. For example, if DTR is supposed to be on all the time but you suspect that DTR is being dropped, you would tell FTS to look only at DTR by checking the DTR box and unchecking the others, and then do a search for where one or more control signals changed from on to off. FTS would search the DTR signal and stop at the first event where DTR dropped from on to off. Searching for an Exact State To search for an exact state means that FTS will find events that match exactly the state of the control signals that you specify. First choose to search for an event where your choices exactly describe the state. This will change the normal check boxes to a series of radio buttons labeled On, Off and Don t Care for each control signal. Choose which state you want each control signal to be in. Choose Don t Care to have FTS ignore the state of a control signal. When you click Find Next, FTS will search for an event that exactly matches the conditions selected, beginning from the currently selected event. If the end of the buffer is reached before a match is found, FTS will ask you if you want to continue searching from the beginning. If you want to be sure to search the entire buffer, place your cursor on the first event in the buffer. Example If you need to find an event where RTS, DSR and DTR are on, CTS is off and you don t care about the state of CD and RI, you would set the buttons as illustrated. 36

37 Search by Pattern Search by Pattern lets you to do a traditional string search. You can search one or both sides of the circuit, and your search can include wildcards. You can combine any of the formats when entering your string. Entering Characters Place the cursor in the Pattern box and type in your string. Click Find Next in order to find the next occurrence of the string. You can click on Find Next as many times as necessary until FTS has searched all the data. Clicking on Find Previous will search the buffer backwards. You can enter any character from a character set, with the following exceptions: \$&^?. These characters are used as prefixes to let you to enter hex, binary, control or wildcard characters. The escape character is the backslash \. Use this character when you want to search for one of the above restricted characters. For example, to search for a $, you would enter \$. To search for a \, enter \\. Check Ignore Case to do a case-insensitive search. Entering Hex or Binary To enter a hex value, enter a $ followed by two hex digits. For example, to search for hex 00 01, enter $00$01. If you need to specify the $ as a character, use \$. Just as the $ symbol tells FTS that the following characters are hex digits, the & symbol tells FTS that a binary number comes next. For example, to search for binary , you would use & If you need to specify the & as a character, use \&. 37

38 Entering Control Characters The ^ (caret) is used to enter the control characters Ctrl-A through Ctrl-Z and Ctrl-@,[,\,],- when using the ASCII character set. For example, ^A specifies Ctrl-A ($01) and ^@ specifies ASCII NUL ($00). If you need to specify the ^ as a character, use \^. Note that neither the ^ character nor control characters exist in Baudot, so attempts to search for the ^ character will result in an error message. The ^ character exists in EBCDIC, but control characters do not. A search for ^A in EBCDIC will match any occurrence of ^A ($5F$C1). You do not need to use the escape character to search for a ^ character in EBCDIC. Using Wildcards The wildcard character is the?. FTS supports wildcard searching at the byte, nibble and bit level. Wildcards can be used in place of characters, hex digits, and binary digits. If you need to specify the? as a character, you can use \?. Examples: To search for any single byte in the range of hex $10 through $1F, type $1?. &111111?? will search for binary numbers beginning with and ending with any combination of 1 and , , , and are all strings that match the search criteria. To search for any four character string which starts with an L and ends with an ES, type L?ES. You can combine formats in one string. For example, another way to specify a search for the string L?ES is $4C&????????& S. Searching By Time Absolute vs. relative timestamp searches An absolute timestamp search means that FTS will search for an event at the exact date and time specified. If no event is found at that time, FTS will go to the nearest event either before or after the selected time, based on the "Go to the timestamp" selection. A relative search means that FTS will begin searching from whatever event you are currently on, and search for the next event a specific amount of time away. Use the radio buttons to indicate which type of search you would like to do. Absolute Timestamp Search Specify the time to search for using the counters in the middle of the window. Click on the arrows next to each item to increase or decrease the value of each counter. By default, the counters are filled in with the timestamp of the first event in the buffer. When you have finished selecting the time to search for, click on the Go To button to start the search. Sometimes there can be more than one event with the same timestamp. FTS will highlight all events with the same timestamp. Relative Timestamp Search 38

39 Click on the event in the Review Events window that you want to begin the search from. The event must have a timestamp in order for relative timestamp search to work. In the Find window, use the counters in the middle of the window to specify the time interval you want to jump. You can specify intervals in days, hours, minutes, seconds, and fractions of a second, or any combination of these. When you have specified the time interval you want to use, click on the Move Forward or Move Backward buttons to start the search from the current event. For example, to search for an event occurring 10 seconds after the currently selected event, choose to do a relative timestamp search, use 10 seconds for your time interval, and click on Move Forward. As with absolute timestamping, FTS will highlight all events with the same timestamp. Choosing "On or Before" or "On or After" FTS will search for an event that matches the time specified. If no event is found at that time, FTS will go to the nearest event either before or after the specified time. Choose whether to have FTS go to the nearest event before the specified time or after the specified time by clicking the appropriate radio button in the "Go to the timestamp" box. If you are searching forward in the buffer, you will usually want to choose the "On or After" button. If you choose the "On or Before" option, it may be that FTS will finish the search and not move from the current byte, if that byte happens to be the closest match. Subtleties of Timestamp Searching Timestamping can be turned on and off while data is being captured. As a result, the capture buffer may have some data with a timestamp, and some data without. When doing a search by timestamp, FTS will ignore data without a timestamp. Go To Event This type of search allows you to go to a particular event, or to move through the data X number of events at a time. You can move either forward or backwards through the data. To go to a particular event, simply click in the box to place the cursor, and type in the number of the event you want to go to. Then click on the Go To button. To move forward or backwards through the data, type in the number of events that you want to move each time, and then click on the Move Forward or Move Backward button. For example, to move forward 10 events, type the number 10 in the box, and then click on Move Forward. Each time you click on Move Forward, FTS will move forward 10 events. Side Restriction Side Restriction means that FTS will look for a pattern coming wholly from the DTE or DCE side. If you choose to search without regard for data origin, FTS will look for a pattern coming from one or both sides. For example, if you choose to search for the pattern ABC and you choose to search without regard for data origin, FTS will find all three instances of ABC shown below. 39

40 The first pattern, with the A and the C coming from the DTE device and the B coming from the DCE is a good example of how using a side restriction differs from searching without regard to data origin. While searching without regard for data origin will find all three patterns, searching using a side restriction will never find the first pattern, because it does not come wholly from one side or the other. If you choose to search for the pattern ABC, and you restrict the search to just the DTE side, FTS will find the following pattern: In this example, FTS will find only the second pattern (highlighted above) because we restricted the search to just the DTE side. The first pattern doesn't qualify because it is split between the DTE and DCE sides, and the third pattern, though whole, comes from just the DCE side. If we were to choose both the DTE and the DCE sides in the above example, FTS would find the second pattern followed by the third pattern, but not the first pattern. This is because each side has one instance in which the whole pattern can be found. FTS will completely search the DTE side first, followed by the DCE side. Side Restriction is available for pattern and error searching. Live Events The Live Events window allows you to view data as it is being captured. The window is continually updated with incoming data (see Data Capture Options to change the rate at which FTS updates the window.) You can freeze the window to view pertinent information while still capturing data in the 40

41 background. To view information on a particular byte, click on the byte and information will be displayed in the three byte information lines at the bottom of the window. Use the Review Events window rather than the Live Events window while capturing data because you can browse through the entire buffer and run searches, which you cannot do from the Live Events window. Using the Review Events window also places less of a processing load on the PC. If you find that you have overrun errors or buffer overflows in your data while using the Live Events window, try reducing the Window Refresh Rate or using the Review Events window instead. See Performance Notes for more information on maximizing performance. The Live Events Toolbar Freeze Display - Freezes the window so you can review a portion of data. Data capture will continue in the background. Click on the button again to unfreeze the window. When you do this, the screen will quickly fill in the data captured since the screen freeze and jump you down to view incoming data again. Options - Brings up the Capture Options window. This window allows you to change the window refresh rate and set startup capture options. Mixed Sides - By default, FTS shows data with the DTE side above the DCE side. This is called DTE over DCE format. DTE data has a white background and DCE data has a gray background. FTS can also display data in mixed side format. In this format, FTS does not separate DTE data from DCE data but shows all data on the same line as it comes in. DTE data is still shown with a white background and DCE data with a gray background so that you can distinguish between the two. The benefit of using this format is that more data will fit onto one screen. Character Only - FTS shows both the number (hex, binary, etc.) data and the character (ASCII, EBCDIC or BAUDOT) data on the same screen. If you do not wish to see the hex characters, click on the Character Only button. Click again to go back to both number and character mode. Number Only - Controls whether FTS displays data in both character and number format, or just number format. Click once to show only numeric values, and again to show both character and numeric values. All Events - Controls whether FTS shows all events in the window, or only data bytes. Events include control signal changes and framing information. Font Size - Brings up the Font Dialog box, allowing you to change the font size. Capture Options Window Refresh Rate FTS s first priority is capturing all the data that comes through the ports. Its second priority is updating the screen to reflect the new data. This option sets the rate at which FTS will update the screen. The default setting is once every 1000 milliseconds, or once every second. Changing the rate to a slower update rate will give the computer more time to process incoming data. This can help ensure that FTS captures all the data if you are monitoring a high speed circuit with a lot of data on it. However, it also means that the screen update might look a bit jerky. 41

42 Changing the rate to a faster rate will make the screen update more smoothly, but puts an increased processing load on your PC. This can cause FTS to drop data, resulting in overrun errors and/or buffer overflow errors. If FTS is dropping data, try changing the rate to a slower update rate. 42

43 Reviewing Control Signals Signal Display Window The Signal Display window provides you with a graphical view of control signal transitions that you can manipulate. You can zoom in to view the state of control signals for a range of events, or zoom out to view control signal changes over the course of an entire capture session. The Signal Display window does not provide a real-time view of control signal changes. It is intended to be used as a post-process review screen. Use the Breakout Box window to view real-time control signal changes. Note that if you bring up the Signal Display window while data is being captured, the window will show you the state of the control signals at the time the window was opened. This is called a "snapshot" because it is a picture of the buffer at the time the Signal Display was opened. To update the display to reflect the current state of the buffer, use the New Snapshot button. The Signal Display window will display only the control signals you are interested in. Click the Options button to choose which control signals to display. Reading the Signal Display Control signal changes are displayed in a graphical format. On the left side of the screen is a list of the signals currently being displayed, and to the right of each name is a line displaying the state of the signal over time. A single line means that the signal was logically off, while a double line means that the signal was logically on. Dotted lines are used for signals that were not present at the time of capture. For example, if you are monitoring a circuit that does not use CD, that line will appear as a dotted line in the control signal display. The four information lines at the bottom of the window tell you what events are being shown in the window, and where you are in relation to the buffer as a whole. The first line tells you what event numbers are in the current snapshot, the total number of events, and the amount of time that passed between the first event in the snapshot and the last event (called Delta). The second line gives the same information about the events that are currently visible in the window. Because you can zoom in and out, often the events being shown in the window are not the same as the number of events in the current snapshot. The third line gives the same information for the currently selected events. You can highlight a range of events by clicking at any point on the graphical display and dragging the mouse to the left or the right. The third line will show information for the selected range. The fourth and last line shows the exact timestamps of the first and last bytes in the currently selected range. Note that this does not tell you the timestamp for the entire snapshot or the events displayed in the window, just the highlighted events. A single mouse click will place the cursor in the window. FTS highlights all six signal changes in one color, and uses a different color to specify the control signal line clicked on. You can highlight a range by clicking and dragging the mouse to the right or left. You can also use the arrow keys to move the cursor to the right or left. The Signal Display window is synchronized with other windows in FTS. A range highlighted in the Signal Display window will also be highlighted in the Review Events, Frame Decode and Frame Summary windows. 43

44 The Snap to Nearest Change button lets you place the cursor on the signal change you want to look at without needing to click on exactly the right spot. Find the line corresponding to the control signal you want to look at. Click on the line, and FTS will move the cursor to the nearest change. If you highlight a range, FTS will "snap to" the nearest changes on either side. This feature is active when the Snap To button is pressed, and inactive when the button is not pressed. Use the Zoom In and Zoom Out buttons to increase and decrease the magnification of the window. FTS will change the magnification by a factor of 2, 4 or 8, depending on the option selected in the Signals menu. If you want to see a range in greater detail, highlight the range you want to view and click on the Zoom to Selection button. FTS will zoom in to show only that range in the window. If the range is small, FTS may add additional events to fill up the window. To view the entire snapshot in the window, click on the Display Entire Buffer button. Note that if you bring up the Signal Display window while data is being captured, the window will show you the state of the control signals at the time the window was opened. To update the display, use the New Snapshot button. The Signal Display Toolbar Show Control Window - Bring control window to the front. Take New Snapshot - Takes a new "picture" of the capture buffer. If you are capturing data when you open the Signal Display window, the window will show only the state of the control signals that were in the buffer when the window was opened. Click this button to update the window with the contents of the current buffer. Zoom In - "Zooms in" on the signal display. How much you zoom in is determined by your selection in the Signals menu. You can zoom in by a factor of 2, 4, or 8. Zoom Out - Reverse of Zoom In. Zoom to Selection - Zooms to show only the region highlighted on the screen. If the highlighted area contains few events, the Signal Display window may also display additional events in order to fill up the screen. Display Entire Buffer - Zooms all the way out to display the contents of the entire buffer in the window. Find - Opens the Find Control Signal change window. Options - Open the Signal Display options window, where you can change which control signals are displayed in the window. Snap to Nearest Change - Moves the cursor to the nearest signal change whenever you click on the line graphics in the window. Find the line for the control signal whose changes you want to see. Click on that line, and FTS will move to the nearest signal change for that control signal. You can also highlight a range, and FTS will snap to the 2 nearest changes on either side of the range. 44

45 Timestamping Options - Opens the Timestamping Options window, where you can change the timestamping resolution and how timestamps are displayed. Signal Display Options Choose which control signals to display in the Signal Display window. A check mark next to a control signal name means that the signal will be displayed. Click on a box to check or uncheck it. 45

46 Printing Review Events Printing 1. Open the Review Events window. 2. Make sure the data you want to print is displayed in the window. Load a capture file if necessary. 3. From the File menu, choose Print. 4. Choose the correct printer and number of pages, and click OK to begin printing. Print Preview Print Preview shows you how the data will look printed. You can scroll through the pages and zoom in on the data to get a closer look. The line of buttons across the top of the window controls the functions of the window. To open the Print Preview window, choose Print Preview from the File menu in any window that supports printing. When Print Preview is chosen, the preview display replaces the regular data display in the window. You can print directly from the Print Preview window. Click on the Print button to bring up the print window. Use the Next Page and Prev Page buttons to navigate through the data. Next Page will show you the next page in your data will look, while Prev Page will take you back to the previous page. Two Page will change the display to show two pages of data. When in the Two Page display, the button will read One Page. Click on the One Page button to return to viewing one page. Zoom In and Zoom Out allow you to change the magnification of the pages. Click on the Zoom In to increase the magnification, and on Zoom Out to decrease the magnification. When you have reached the limit in either direction, the buttons will be grayed out. You can also zoom in and out by clicking on the page itself. When the cursor looks like a magnifying glass, you can click on the page to increase the magnification. When you have reached the top level of magnification, the cursor will change back to an arrow. Click on the page to return to normal magnification. Click on the Close button to return to the regular display. Troubleshooting Printing Problems Some printer drivers may not be able to handle the FTS True Type fonts correctly in the default mode. When this happens, the printer driver substitutes other fonts for the FTS fonts, resulting in printed data that does not look like the data on the screen. Many printers have several options for handling True Type fonts. Changing how your printer handles True Type fonts can often be done from the Printer Properties box. Printer Properties can be reached by choosing Printers from the Settings menu on the Start button, and then right-clicking on your printer and choosing Properties. It can also be reached from the Print window within FTS. Click on the button labelled Properties next to the name of the printer in the Print window. 46

47 Every printer handles font substitution a little differently, and every printer puts the font settings in a different place. If you cannot easily find the font settings for your printer, please refer to your printer's documentation for help. Export The export feature allows you to export your capture files or capture buffer to text or binary format. Text format is used to create readable text files, which can be printed as is or imported into database programs or spreadsheets. Binary format creates a binary file which can be read by custom applications. The ftsrdexp.h file is a C/C++ header file which will give you the structure of the binary file. You can use this file to write your own data manipulation programs. 1. To begin exporting, go to the Control or Review Events windows, and choose Export from the File menu. 2. Select Text Output to create text files, and Binary Output to create binary files. 3. Select the fields you want included in the export file. Click on a field in the Available Fields box, and then click Add to add the field to the list of Displayed Fields. The Preview Sample box at the bottom of the window will show you what fields you have added and how they will look in the export file. (The Preview Sample window uses dummy data, not actual data from your capture buffer.) 4. Select a filename. The default filename for text files is export.txt for a capture buffer or capture_file_name.txt for a capture file. Similarly, default filenames for binary files end in a.bin extension. Underneath the file name, FTS will show you approximately how big the file will be, and what percentage of free disk space it will take up. 5. Click on the Export button to begin exporting. Depending on the amount of data to be exported, the export process may take some time. By default, your export file will be saved in the Data directory. Click on the Browse want to save the export file to another location. button if you You can choose to export the entire capture buffer or just a portion of it. If you have the Review Events window open and have selected a range in it, the export window will automatically fill in the range for you. Export Fields Available fields are: Byte Number Decimal Char/Event Name Errors Event Number Frame Number Hexadecimal Octal Side Signals Timestamp Type number of the data byte decimal value of the data byte character value of data bytes, or name of non-data bytes includes any errors associated with bytes number of the event (see Event Numbering for why Byte Number and Event Number may be different) number of the frame the event is in hexadecimal value of the data byte octal value of the data byte shows whether the byte originated from the DTE or DCE side gives the state of the control signals shows the timestamp of the event shows whether event was Data or a Special Event (anything other than a data byte) 47

48 Export Filter Out You can filter out data you don't want or need in your text file. In the Filter Out: box, choose to filter out the DTE data, the DCE data or neither side (don't filter any data.) For example, if you choose the radio button for DTE data, the DTE data would be filtered out of your export file and the file would contain only the DCE data. You can also filter out Special Events (which is everything that is not a data byte, such as control signal changes and Set I/O events), Nonprintable characters or both. If you choose to filter out Special Events, your export file would contain only the data bytes. Filtering out the nonprintable characters means that your export file would contain only special events and data bytes classified as printable. In ASCII, printable characters are those with hex values between $20 and $7e. Export Templates Once you've set up an export format, you can save all your options as a template and use it for future exports. 1. To create a template, set up all the options on the export window exactly as you want them to be in the template. 2. Type a name in the Apply Template box, and click Save Template. 3. To retrieve your template, click on the down arrow next to the Apply Template box, and choose your template from the list. To delete a template, choose the template in the Apply Template box, and click the Delete Template button. There are several templates supplied with FTS that cannot be deleted. These are: CSV, Quoted CSV, Transmit DTE, Transmit DCE, Sample Report, and Excel/Access. Other Export Options Use Footer This option is valid only when doing a binary export. If you are exporting a capture file for the purpose of retransmitting the data, uncheck this box. If you will be manipulating the data using the sample export program, check this box. If the data is exported without the footer, the sample export program will not be able to read the export file. Use Abbreviated Event Names Separate Records with CR/LF Align Columns Put Fields in Double Quotes Output Header Check this box to abbreviate the names of the Special Events. This is useful to conserve space in the text file. Specifies whether to separate each record with a carriage return/line feed. If this option is unchecked, the data will be output as a continuous stream. Check this box to have the columns be left-justified. Check this box to put double quotes around the data in each field. Includes a header at the top of the file with the date and time the file was exported, name of the original capture file or capture buffer, and the event numbers and timestamps for the range exported. 48

49 Output Field Name Record Align Field Names with Data Timestamp Format Character Set Includes a record at the top of the file with the field names. Aligns the field name column with the data columns. Sets the timestamp format. Native format is the month/day/year plus hour:minute:second:millisecond AM/PM in twelve hour format. For other formats, "D" stands for day, "H" stands for hour, "M" stands for minute, "S" stands for second and "m" stands for millisecond. Choose ASCII, EBCDIC or Baudot. (See note on exporting Baudot.) Signals Characters Defines how control signal states are indicated. Choose from 1/0, T/F, or X/space. "X", "1" and "T" indicate an "on" or "high" signal state. Errors Characters Field Delimiter Defines how error conditions are indicated. Choose from 1/0, T/F, or X/space. "X", "1" and "T" indicate that an error occurred. Defines how the fields will be separated. Choices are None (no delimiter will be used), Comma, Tab, Space, Bar and Semicolon. If a delimiter is chosen, FTS will include the delimiter between each field in the export file. Export Header File The structure of the binary output file is contained in ftsrdexp.h. This file is a C/C++ header file and is located in the Export Samples directory. The ftsexprt.h file should give you all the information you need about the structure of the binary output file to write a program to manipulate the data. The advantage of choosing binary output over text output is that the resulting file is much smaller than the corresponding text file would be. Exporting Baudot When exporting Baudot, you need to be able to determine the state of the shift character. In a text export, the state of the shift bit can be determined by the data in the Character field. When letters is active, the character field will show letters and vice versa. For binary export, the shift bit is stored in the same byte with the error bits. The location of the shift bit is documented in ftsrdexp.h. Options Line Grade Options The Line Grade provides a quick reading of the overall quality of transmission over the communications link from Excellent to Unacceptable. This allows non-specialists to quickly determine whether a line is 49

50 good or bad without having to interpret a lot of arcane statistics. Error rate thresholds can be defined for each level of line quality. To open the Line Grade Options window, choose Options from the File menu on the Test Setup window, and click the Line Grade tab. Line Grade Threshold There are four Lines Grades: Excellent, Good, Poor and Unacceptable. There are three customizable thresholds to accompany the four grades. Unacceptable does not require a threshold because a Line Grade worse than Poor is Unacceptable. Each Line Grade is assigned an LED color. Excellent is green, Good is blue, Poor is yellow and Unacceptable is red. The LED appears on the Control window status bar and on the Statistics window. Line Grade Actions For each Line Grade there is a choice of actions to take upon transition to or from that Line Grade. Click in the box for the action or actions you would like FTS to take for each Line Grade. Note that you can have more than one action for a Line Grade. Beep will cause FTS to beep once to signal a transition. This is useful if you are running a test and do not want to pay close attention, but want to know when something significant happens. Message will cause a message box to pop up on the screen signaling a transition. Log means that a snapshot of the Statistics window will be written to the log file when the transition occurs. Note that you must open a log file from the Test Setup window in order for the line grade changes to be logged. Stop When Downgrading means that FTS will stop the test when the Line Grade changes from the selected grade to a lower grade. For example, if you check Stop for a Line Grade of Good, FTS will stop the test when the Line Grade changes from Good to Poor or Good to Unacceptable. FTS will not stop the test if the Line Grade changes from Good to Excellent or from Excellent to Good. Similarly FTS will not stop the test if the Line Grade changes from Poor or Unacceptable to Good. Line Grade Units and Low Sample Minutes Line Grade Units defines whether to use Bits, Blocks, or Seconds to calculate Line Grade. For example, if this field is Bits, then the calculation performed is Error Bits/Received Bits. Low Sample Minutes determines how long to wait before calculating Line Grade. In many cases it takes a fair amount of time before enough data has been received to constitute a statistically meaningful sample. Line Grade is displayed as Low Sample until this threshold has been satisfied. Note that the Line Grade threshold is based on received data, not elapsed test time, and that the Line Grade is updated once per minute. Thresholds FTS uses a group of numeric values to categorize the data it receives. For example, a second is a Severely Errored Second if its Bit Error Rate is greater than 1/1000. FTS allows you to define these thresholds yourself. The default values are selected to conform to CCITT Recommendation G.821 and other commonly used standards. 50

51 To open the Thresholds window, choose Options from the File menu on the Test Setup window, and click the Thresholds tab. Sync Loss Thresholds Error Ratio - If the test is In Lock and the Bit Error Rate over the course of 1/18 of a second is greater than this threshold, then a Sync Loss Occurrence is registered, and the test status changes to Out of Lock. Sync Loss Timeout Seconds - If a test is In Lock and no data is received for an interval greater than this threshold, then a Sync Loss Occurrence is registered, and the test status changes to Out of Lock. This time is also used in Half Duplex Mode to determine how long to wait for data before switching from receive mode to transmit mode. G.821 Thresholds Severe Error Seconds - If the Bit Error Rate over the course of a second is greater than this threshold, the second is counted as a Severe Error Second. Degraded Minute - If the Bit Error Rate over the course of a minute is greater than this threshold, the minute is counted as a Degraded Minute. Available/Unavailable Seconds - Received Data must be either Severely Errored or not Severely Errored for the number of consecutive seconds specified by this threshold to cause a transition between Available and Unavailable Seconds. Control Signal Options The Control Signals options allow you to change the default behavior for each control signal. There are five options available. To open the Control Signal Options window, choose Options from the File menu on the Test Setup window, and click the Signals tab. Always On Always Off On for Test raise the signal and keep it raised. lower the signal and keep it lowered. raise the signal only while a test is running, otherwise lower it. On for Modem Commands raise the signal only when sending a command to the modem, otherwise lower it. This occurs whenever a button is pressed that sends a modem command (such as Local Loopback or Auto Answer) or when the Terminal window is open. On for Test and Modem Commands raise the signal when a test is running, when sending a command to the modem or when the Terminal window is open, otherwise lower it. Transmit Options The Transmit Priority determines how much of a priority the system places on transmitting data versus updating the screen. On slower PC's, so much processor time can be taken up transmitting data, especially at higher data rates, that the screen never updates, making it appear that the PC has locked up. The Transmit Priority slider bar determines how much time to take transmitting data. When the Transmit Priority is high, FTS will ensure that data gets transmitted before it updates the user interface. If the Transmit Priority is low, FTS will allow the user interface more time. 51

52 System Settings Open the System Settings box by choosing System Settings from the File menu on the Control Window. To enable a setting, click in the box next to the setting to place a checkmark in the box. To disable a setting, click in the box to remove the checkmark. Common Options Save Windows on Exit When enabled, FTS will remember which windows were open and how they were arranged, and put all the windows back in the same position the next time FTS is started. Buffer/File Options Capture Buffer Size (in K) BERT Buffer Size (events) Enter the maximum size of the capture buffer. If you enter a number larger than the maximum allowable size, FTS will warn you and automatically set the size to the maximum allowable size. Enter the maximum size of the BERT buffer. Increasing the value of this field may help prevent BERT buffer overflow errors. Note: FTS does not actually use 100% of available memory for the capture buffer. By default, FTS will limit the maximum size of the buffer to 50% of the available resources. We strongly recommend not changing this percentage unless absolutely necessary. If you do need to use more resources, you can change the maximum percentage in the Advanced Options window. Click the Advanced button on the System Settings window. If you want to change the maximum percentage for the buffer, find the setting for Max Percent of Available Virtual Memory Used for Capture Buffer. We strongly recommend not setting this option to 100%, as this will take all your system resources, leaving none for any other application. Advanced System Options These parameters affect fundamental aspects of the software, and it is unlikely that you will ever have to change them. If you do change them and need to return them to their original values, the default value is listed in parentheses to the right of the value box. Most technical support problems are not related to these parameters, and as changing them could have serious consequences for the performance of FTS, we strongly recommend contacting technical support before changing any of these parameters. Max Percent Of Free Disk Space for Capture File This setting determines what percentage of free hard drive space can be used for the capture file. By default, FTS will limit the maximum size of the capture file to 50% of the available space on the hard drive. If you need to create a larger capture file than the current settings allow, increase this percentage. Then go back to the System Settings window and increase the maximum file size. Max Percent Of Available Virtual Memory Used for Capture Buffer This setting determines what percentage of available virtual memory can be used for the capture buffer. By default, FTS will limit the maximum size of the buffer to 50% of the available virtual memory. Increasing this percentage will give you a larger capture buffer, but will leave less virtual memory available for other applications. Driver Receive Buffer Size in Operating System Pages This is the size of the buffer used by the driver to store incoming data. This value is expressed in operating system pages. In Windows 95, an operating system page is 4K. 52

53 Driver Action Queue Size In Operating System Pages This is the size of the buffer used by the driver to store data to be transmitted. This value is expressed in operating system pages. In Windows 95, an operating system page is 4K. Capture Buffer Read Cache Size In Kbytes Sets the size of the capture buffer cache. This setting is important when reading data. A larger buffer may mean faster read times. Capture File Write-Through Cache Size In Pages Sets the size of the capture buffer write cache. This setting is important when writing data to disk. Return Unused Space in Capture File When Closing (Yes/No answer) When FTS opens a capture file, it allocates as much disk space as it needs for the maximum capture file size. When the capture file is closed, FTS gives back any unused space. This process can take some time if the maximum capture file size is large. This setting is the threshold that determines if we give back unused space when the file is closed. The default value of "checked" means that FTS will always give back unused space. If unchecked, FTS will not return unused space, which may result in very large, mostly empty capture files. Maximum Number of Bytes Decoded Per Frame This is the largest frame size that FTS will attempt to decode. This is used to prevent FTS from attempting to decode very large bad frames. This number should be large enough to ensure that the largest reasonable frame is handled completely. Maximum Number of Bytes Used to Store Supplementary Capture File Information Sets the amount of space used to store supplementary information in the capture file. The default value is bytes. Capture Buffer System Page Size Multiplier Data in a capture file is indexed by pages to allow for faster retrieval. The page size multiplier determines how often the file is indexed. The default value of 1 means that the capture file is indexed once every page, or once every 4K. Non-Realtime Event Queue Size This is the queue for all non-realtime events. To open this window Choose System Settings from the File menu on the Control window, and then click the Advanced button. 53

54 Technical Information Contacting Technical Support Technical support is available in several ways. The answers to many questions can be found in the online help. Frontline s web site has documentation on common problems, as well as software upgrades and utilities to use with our products. Web: go to the Technical Support Area FTP Site: ftp.fte.com address: tech_support@fte.com If you need to talk to a technical support representative, support is available between 9am and 5pm, Eastern time, Monday through Friday. Technical support is not available on national holidays. Phone: Fax: The FTS Driver FTS uses custom versions of the standard Windows serial drivers in order to capture data. How the drivers are loaded differs depending on the operating system. See below to find out more information for your operating system. Windows 95/98 Driver FTS uses a custom driver that is compatible with serial.vxd, the standard serial driver supplied with Windows 95/98. The FTS driver is called serial9x.fts and is found in the Frontline Test System directory. When FTS starts, it checks the serial.vxd driver in the Windows\System directory to see if the driver is Frontline s or not. If serial.vxd is not Frontline s driver, FTS makes a backup copy of the driver called serialvxd.standard and puts it in the Frontline Test System directory. It then copies serial9x.fts to the Windows\System directory and renames it serial.vxd. If FTS finds that serial.vxd is actually Frontline s driver, FTS displays a warning message explaining that Frontline s driver is being used as the standard driver. The warning message lets you know that for one reason or another, Frontline s driver was not removed from the Windows\System directory the last time FTS shut down. To summarize, before FTS starts up, the driver in the Windows\System directory is called serial.vxd and usually is the standard driver supplied by Microsoft. This driver is approximately 19K in size. After FTS starts up, the driver in the Windows\System directory is still called serial.vxd, but is Frontline s version of the driver, which is larger than Microsoft s driver. In the Frontline Test System directory are two files, serial9x.fts (another copy of the Frontline driver) and serialvxd.standard, which is the original driver. When you exit FTS, this process is done in reverse, putting the original driver back into the Windows\System directory and removing Frontline s driver. In this way, the Windows\System directory is kept clean. FTS keeps a copy of the original driver in the Frontline Test System directory. If the driver swap procedure does not complete normally, you might have to make sure that all drivers are back in the proper place. If the only problem is that the drivers never got switched on exiting, you can start 54

55 FTS, note the warning message, and then exit normally. This will put your original driver back in the Windows\System directory. If your original driver becomes corrupted, a copy of the driver is kept in the Frontline Test Sytem directory and is called serialvxd.standard. You can copy serialvxd.standard into your Windows\System directory and rename it serial.vxd. If your Frontline driver becomes corrupted, you can reinstall the software from the distribution disks, or call Frontline for assistance. Windows NT Driver FTS uses a custom driver which is compatible with serial.sys, the standard serial driver supplied with NT. The FTS driver is called serialnt.fts and is found in the Frontline Test System directory. In Windows NT, the serial driver is automatically started when NT starts. In order for Frontline's driver to be started, the standard driver must be "stopped" first. When FTS opens, it issues a Stop command to the standard serial driver. If the stop is successful, FTS makes a backup copy of the standard driver, calls it serialsys.standard and puts it in the Frontline Test System directory. It then copies serialnt.fts to the Winnt\System32\drivers directory and renames it serial.sys. Once Frontline's driver is in place, FTS issues the command to start the driver before bringing up the user interface. When you exit FTS, this process is reversed. FTS stops Frontline's driver, puts the standard driver back into the Winnt\System32\drivers directory and starts the standard driver. In this way, the Winnt\System32\drivers directory is kept clean and the machine returned to its original state. FTS keeps a copy of your standard driver in the Frontline Test System directory. The above process is what occurs if no other applications are using the serial driver at the time FTS is opened or closed. However, if other applications are using the driver when FTS tries to stop it, things are more complicated. If another application is using the serial driver when FTS issues the Stop command, NT will wait until the application using the driver is finished before executing the Stop. FTS checks to see if the driver has stopped before beginning the driver switch process. If FTS sees that the serial driver has not been stopped, it displays a message box saying that it was unable to stop the serial driver and then it will exit. The complication is that once the Stop command is issued, there is no way to retract it. This means that when all applications are finished with the serial driver, NT will stop the driver. If you try to start FTS while another application is using the serial driver, FTS will issue the Stop command, see that the driver is still loaded and close itself, but the Stop command will still be executed when the other application is finished. In order to use any serial devices after this, you will have to manually restart the serial driver. Note that if you close the other application and restart FTS, it will recognize that there is no driver loaded, and go ahead and load its own. Similarly, if you start FTS, and then start another application that uses the serial driver, both FTS and the other application will be using Frontline's driver. If you close FTS while the other application is still running, FTS will issue the Stop command to stop the Frontline driver and execute the driver switch. FTS checks to see if the Frontline driver has been stopped. If not, FTS displays a warning message. When the other application using the driver exits, NT will stop the serial driver. In order to use any serial devices after this, you will need to manually restart the serial driver. Note that if you restart FTS, it will recognize that there is no driver loaded, and go ahead and load its own. Restarting the serial driver 1. Click on the Start button, and choose Settings -> Control Panel. 2. Double-click on the Devices icon. 3. Select the Device called "Serial" and then click the Start button. 55

56 If your original driver becomes corrupted, a copy of the driver is kept in the Frontline Test Sytem directory and is called serialsys.standard. You can copy serialsys.standard into your Winnt\System32\drivers directory and rename it serial.sys. If your Frontline driver becomes corrupted, you can reinstall the software from the distribution disks, or call Frontline for assistance. Windows 2000 Driver FTS uses a custom driver which is compatible with serial.sys, the standard serial driver supplied with Windows The FTS driver is called serialnt.fts and is found in the Frontline Test System directory. During installation, FTS installs its version of serial.sys to the winnt\system32\drivers directory. A utility is also installed which can uninstall or install the serial driver at any time without going through the installation program. You may need to uninstall the serial driver if you suspect that it is not working properly with another application. You may need to install the serial driver if you recently upgraded your operating system and had FTS already installed on the previous operating system, or if you installed your product from the FTS Setup tab. To uninstall the serial driver manually, go to the Start menu and choose Programs -> Frontline Test System -> Windows 2000 Serial Driver Support -> Uninstall FTS Serial Driver. This will remove Frontline s driver and restore the original serial.sys driver. To install the serial driver without going through the installation program, go to the Start menu and choose Programs -> Frontline Test System -> Windows 2000 Serial Driver Support -> Install FTS Serial Driver. This will make a backup copy of the original serial driver and put Frontline s driver in place. You will need to reboot your PC after running the installation utility. Note: Frontline's driver is not yet fully compatible with the Windows 2000 driver. Frontline's driver does not provide the plug and play or power management features of the Windows 2000 serial driver. This functionality will be added in a future release. We strongly suspect that support for PCMCIA serial cards will not be available under Windows 2000 when using Frontline's driver. Support for built-in serial ports appears to be fine. Performance Notes As a software-based product, the speed of your computer s processor affects FTS s performance. Overrun errors and buffer overflows are indicators that FTS is unable to keep up with the data coming in. The information below describes what happens to the data as it comes in the port, what the two types of errors mean, and how various aspects of FTS affect performance. Also included are suggestions on how to improve performance. Data captured by the serial port first goes into the buffer of the UART chip of the serial port. The UART generates an interrupt, which tells the FTS driver to check the port. The driver takes the data from the UART and counts each byte as they are put into the driver s own buffer (called the Driver Buffer on the Statistics window.) The driver tells FTS that data is ready to be processed. FTS takes the data from the driver s buffer and puts the data into the BERT buffer. UART Overrun errors occur when the data in the buffer of the UART is not retrieved before new data comes in. In this case, FTS knows that it has lost information but it does not know how much. FTS indicates overrun errors in the Statistics window in the UART Overrun Error field. Driver buffer overflow errors occur when the data in the buffer of the driver is not retrieved before new data comes in. Since the driver counts the bytes as it retrieves them from the UART, it not only knows that it has lost data, it also knows how much. Driver buffer overflows are indicated on the Statistics window in 56

57 the Driver Buffer Overflow field. They are also indicated in the Review Events window by a plus sign within a circle. Clicking on the buffer overflow symbol will show how many events have been lost. After the driver has placed the data into the driver buffer, FTS retrieves it from the driver and places it into the BERT buffer, where it is processed. This is where error detection occurs and where all the statistics for the Statistics window are generated. The Unprocessed Events counter at the top of the Statistics window shows how many events remain unprocessed in the BERT buffer. Both overrun errors and buffer overflows indicate that data is coming in too quickly for FTS to process. There are several things that you can do to try and solve this problem. 1. FTS s number one priority is transmitting and capturing data; updating windows is secondary. However, updating windows still takes a certain amount of processor time, and may cause FTS to lose data while the window is being updated. Some windows require more processing time than others, because the information being displayed in them is constantly changing. These windows are (in rough order of processing time taken): Live Events, Breakout Box, Statistics, and Review Events. Close some or all of the above windows while FTS is actively running a test. FTS can run a test with no windows other than the Control Window open. 2. Increase the value of the window refresh rate for any windows you have open while running a test. This will decrease the frequency of window updates, leaving more time for capturing data. Changing the refresh rate can be done from the Options screen in each window. 3. Close all other programs that are doing work while FTS is running. Refrain from doing searches in the Review Events window or other processor intensive activities while FTS is capturing data. 4. For Driver Buffer Overflows, change the size of the driver buffer. This value is changed from the Advanced System Settings window. First, go to the Control Window and choose System Settings from the File menu. Click on the Advanced button. Look for the value called "Driver Receive Buffer Size in Operating System Pages". Take the value listed there and double it. You will need to exit FTS and restart for the change to take effect. NOTE: This procedure might help buffer overflow errors, but will not help overrun errors. 5. For BERT Buffer Overflows, change the size of the BERT buffer. This value is changed from the System Settings window. Choose System Settings from the File menu on the Control window. Increase the value for BERT buffer. You will need to exit FTS and restart for the change to take effect. 6. For UART Overrun errors, try increasing the depth of the FIFO buffers. See FIFOs and FTS for more information. 7. If possible, reduce the baud rate. If you are still experiencing overruns and/or buffer overflows after trying all of the above options, then you may need to use a faster PC. Note Concerning Ring Indicator There is a special case involving Ring Indicator (RI) and computers with 8250 UARTs or UARTs from that family where the state of RI may not be captured accurately. Normally when a control signal changes state from high to low or low to high, an interrupt is generated by the UART, and FTS goes to see what has changed and record it. Ring Indicator works a little differently. An interrupt is generated when RI changes from high to low, but not when RI changes from low to high. If Ring Indicator changes from low to high, 57

58 FTS will not know that RI has changed state until another event occurs that generates an interrupt. This is simply the way the UART works, and is not a deficiency in the software. To minimize the chance of missing a Ring Indicator change, FTS polls the UART every millisecond to see if RI has changed. It is still possible for FTS to miss a Ring Indicator change if RI and only RI changes state more than once per millisecond. UARTs in the 8250 family include 8250s, 16450s, 16550s and variants. If you have any questions about the behavior of your UART and Ring Indicator, please contact technical support. Handy Character and Other Tables ASCII Codes EBCDIC Codes Communication Control Characters Listed below in alphabetical order are the expanded text meanings for common ANSI communication control characters, and FTS s two-character abbreviation for each one. Some abbreviations have forward slash characters between the two letters. This is to differentiate the abbreviations for a control character 58

59 from a hex number. For example, the abbreviation for Form Feed is listed as F/F, to differentiate it from the hex number FF. Abbreviation Control Text Character AK ACK Acknowledge BL BEL Bell BS BS Backspace CN CAN Cancel CR CR Carriage Return D/1-4 DC1-4 Device Control 1-4 D/E DEL Delete DL DLE Data Link Escape EM EM End of Medium EQ ENQ Enquiry ET EOT End of Transmission E/C ESC Escape E/B ETB End of Transmission Block EX ETX End of Text F/F FF Form Feed FS FS File Separator GS GS Group Separator HT HT Horizontal Tabulation LF LF Line Feed NK NAK Negative Acknowledge NU NUL Null RS RS Record Separator SI SI Shift In SO SO Shift Out SH SOH Start of Heading SX STX Start of Text SB SUB Substitute SY SYN Synchronous Idle US US Unit Separator VT VT Vertical Tabulation 59

60 Baudot Codes FIFOs and FTS UARTs, which are the chips that transmit and receive data on serial devices, may or may not come with onboard FIFOs, which are buffers that hold a certain amount of data. The advantage of FIFOs is that they allow the chip to receive several bytes of data before generating an interrupt. This means that the central processor is interrupted less often, allowing it to do more work elsewhere, and also helps prevent data loss if the processor can't retrieve the data from the port immediately. Running a BERT is a processor intensive task, and therefore it is more efficient to run a BERT with the FIFOs on the UART enabled. However, not all UART chips have FIFO buffers. Use the Info button on the Hardware Settings window to find out if your serial port UARTs have FIFO buffers. If they do and you 60

61 are experiencing performance problems (dropped data being the most common), check that the FIFOs are enabled and set to optimum levels. How to set the FIFO buffers in Windows 9x 1. Click the Start button and choose Settings -> Control Panel. 2. Open the System Control Panel. 3. Click on the Ports folder to open it, and double-click on the serial port you want to change. 4. Choose the Port Settings tab and click on the Advanced button. 5. Check that the Transmit buffer is set to the highest level, and the Receive buffer is set to one notch below the highest level. How to set the FIFO buffers in Windows NT In Windows NT, you cannot set the depth of the buffers, but you can ensure that they are turned on. 1. Click the Start button and choose Settings -> Control Panel. 2. Open the Ports Control Panel. 3. Select the port you want to change, and click Settings. 4. Click Advanced. 5. Check that the FIFOs Enabled check box is checked. Unprocessed Events Unprocessed Events is a troubleshooting tool used to determine if the PC running FTS is able to keep up with the flow of data. Data received by FTS is placed into the BERT buffer. It is then processed and the Statistics window updated. If the PC is unable to process events quickly enough, FTS will fall behind. The Current value in the Unprocessed Events field shows the number of unprocessed events remaining in the BERT buffer, which is an indication of how far behind FTS is. It is normal for the Current value to not be zero. If Windows performs some other task while a test is running (for example, opening another application), the Current value will likely increase, but then decrease when the other task is finished. It is not normal for the Current value to be continuously increasing. The Max value is the peak value of unprocessed events. If FTS falls too far behind, it is possible that the data in the buffer will wrap before it is processed. In this case, FTS recognizes that it can't catch up and displays a message indicating that it is unable to process all the events in the buffer, and increments the BERT Buffer Overflow counter. If the Current value increases but drops back down to zero, this is ok. It means that your PC is able to keep up with the data, but just barely. It may help to close any other applications and refrain from doing processor intensive tasks, such as logging, while a test is running. It may also help to lower the Transmit Priority, which governs how much time is spent transmitting events vs. doing other tasks, such as updating windows and processing events. If the Current value continues to increase, eventually the buffer will wrap and FTS will skip data, producing invalid test results. If the Current value increments very slowly, it may be possible to improve performance by closing other applications and FTS windows or lowering the Transmit Priority. You can also increase the size of the BERT buffer. If FTS still falls behind, you will need to lower the data rate or use a faster PC. 61

62 Disabling Control Signal Interrupts Check the Disable Control Signal Interrupts box on the Hardware Settings window to disable processing of control signals. This option is used as a troubleshooting device on circuits where a control signal lead is toggling too quickly for FTS to keep up with. The result is that FTS spends all its time processing signal interrupts and no time updating the user interface, giving the appearance that the computer has frozen. Check this box only on advice of technical support. FTS always checks the state of the control signals when retrieving a data byte, so the Breakout Box will still show control signal changes provided data is being received. However, FTS will not capture control signal changes that occur independent of data bytes when interrupt processing is disabled. FTS polls for control signal changes in Source DTE No Cables mode, Spy and SerialBERT in order to catch Ring Indicator changes. This polling will still occur when interrupt processing is disabled, which means that FTS will capture control signal changes that occur independent of data, but may not capture them at the exact moment the change occurred. It also means that it is possible for FTS to miss a change if the signal changes state twice in a short period of time. 62

63 Bit/Block Error Rate Testing Overview If you are not familiar with BERT/BLERT testing, a brief explanation follows. Bit/Block Error Rate Testing is a technique used to determine the quality of communication links. A known bit pattern is sent from FTS, through a communication link, and looped (echoed) back to FTS. FTS then compares the bits received with the bits sent. A bit is in error when it has changed (inverted) somewhere in the communication link. For example, if was sent, and was received, there would be two errors in the received data. Bits are sent out in groups called blocks. A block error means that the block contains at least one bit error. Event if a block contains many bit errors, this is still only considered one block error. Your particular communication application determines whether you are more concerned with bit errors or block errors. The illustration below shows how to test two modems and a phone circuit. If an unacceptable number of errors is reported, the next step is to determine the cause of the errors. First, test the modems. To test a local modem, use the following set up. If the modems check out, the next step is to determine which part of the phone circuit is causing the bit errors, the outgoing part or the incoming part. This is accomplished using two FTS packages. Reported errors are always based on received data. Therefore if the local FTS reports errors, it implies that the data received by the local modem from the remote FTS was corrupted by the phone circuit. Note that if you want to use FTS in this fashion you must purchase two packages. 63