RangeWizard User Guide v1.0. User Guide. v1.0. Summerour Robotics Corp ( RangeWizard Copyright

Transcription

1 User Guide v1.0 1

2 Introduction: The RangeWizard was developed to offload the timing overhead required to query the popular robotic ultrasonic based sensors, such as the MaxSonar EZ line and Devantech SRF sonars. This frees your microcontroller and or other controller (e.g. PC104, PC, Laptop) to use valuable interrupts and CPU cycles to perform other timing functions. The RangeWizard takes care of all of the sensor timing, and can report the readings in microseconds, inches, or centimeters. The RangeWizard has the ability to query up to 10 ultrasonic sensors, and 6 analog sensors. The ultrasonic/sonar modules can be the single control line type like the Parallax Ping, or the trigger/echo type like the Max Sonar EZ line. Additionally, there are 6 analog lines which can be used for any 5V analog senors, like the Sharp line of infrared sensors. Since the MaxSonar EZ ultrasonic sensors feature an analog interface, you can connect 6 additional sensors to the analog port, giving you the ability to query up to 16 MaxSonar EZ sensors. The following sensors can be queried from the RangeWizard: Supported Sensors Maxbotix Devantech Parallax Analog Sensors MaxSonar EZ0/EZ1/EZ2/EZ3/EZ4 SRF02/SRF04/SRF05 Ping))) Sharp IR Distance, Temp, Other variable voltage type sensors Communication Interfaces: The RangeWizard has both Serial and I2C interfaces, which can be easily integrated to your microcontroller/pc/pda. I2C Interface: The RangeWizard acts as an I2C slave device, and can be connected to, and queried from, any I2C Master (e.g Serializer). The default I2C address for the RangeWizard is 0x6E (110d). When utilizing the I2C interface, all of the ultrasonic readings are returned in response to a single query command. The analog readings can also be returned in the same response as the ultrasonic readings or in a response by themselves (via a simple serial command). I2C commands can be found in the protocol section below. The picture below depicts the RangeWizard connected to the I2C port of our Serializer WL Robot Controller. The RangeWizard can also be powered over the I2C bus as well. 2

3 Figure 1 - RangeWizard connected to Serializer WL via I2C bus Serial Interface: You can communicate with the RangeWizard serially at baud (8 data bits, 1 stop bit, no parity, and no flow control). It can be configured for faster baud rates as well (listed in serial protocol section below). When utilizing the serial interface (using one of the serial interface modules below), the board can be queried for individual ultrasonic and analog sensor readings, or, set in "Streaming" mode where the sensor readings are constantly sent out as fast as possible. Serial Communication Modules: Each serial interface module below quickly plugs into the base RangeWizard board, and communication w/ the board can be established in less than a minute. Having pluggable serial modules means you'll be able to swap the modules in/out, and you won't be stuck with a single interface. This is a great feature, especially if you plan on using the RangeWizard to control various projects in the future. NOTE: Only one serial interface can be used at a time with the RangeWizard. 3

4 Figure 2 - RangeWizard with USB Module Figure 3 - RangeWizard with Bluetooth Module Figure 4 - RangeWizard with XBee Module Figure 5 - RangeWizard with RS-232 Module RangeWizard Pinout The diagram below shows the various ports on the RangeWizard. The Ultrasonic/Sonar header contains 10 individual ports, where each port features a Gnd, Vcc, Trig, and Echo pin. Ultrasonic sensors will connect to this port, which works for both single and dual Trigger/Echo type sensors. Make sure you don t swap polarity (Vcc and Gnd) when connecting the sensors! We do not warranty against such misuse. The Trig pin is the Trigger pin used to trigger the ultrasonic sensors to start ranging, and the Echo pin is used to measure the resulting distance. The Analog header contains 6 individual, 8 bit ports, where each port features a Sig, Vcc, and Gnd pin. Any 3 5V analog sensor can be connected to this port, and queried via the protocol. The Sig (or Signal) pin is the output voltage pin coming from the analog sensor into the RangeWizard. Additionally, the I2C port has Vcc Sda, Scl, and Gnd pins, and requires no pull up resistors since it acts as a slave device. The dual vertical thin headers at the Serial Module Port are used to plug in the serial interface modules (Make sure you have them oriented correctly! see images above). 4

5 External power can be applied at the green screw terminal as shown below. Make sure you don t swap polarity (Vcc and Gnd) when connecting the power supply! We do not warranty against such misuse. There is also a power LED that lights up when power is applied to the board. Figure 6 - RangeWizard Pinout 5

6 Connecting Sensors Connecting the various sensors is very easy; just make sure you watch polarity when you plug them in. Figure 7 - MaxSonar-EZ1 Pinout Figure 8 - Ultrasonic and Analog Sensor Pinout 6

7 Establishing Serial Communications: Depending on the method you re using to communicate w/ the Range Wizard, you can test communications using several methods. The easiest way is to use a Hyperterm type application where you can send the serial commands directly to the RangeWizard. If Hyperterm isn t available, then we su ggest the use of PuTTY, which is free. For Vista users, this will be a must, as Hyperterm isn t distributed with Vista. It s also easy to develop a simple application that opens up a single serial port (configured w/ the proper baud rate, port name, etc.) and sends the commands to the board/processes the responses. Below are several scenarios where serial communications can be leveraged. Establishing I2C Communications All that is required to establish I2C communications is connect the Sda, and Scl pins between the I2C Master and the RangeWizard, along with Vcc and Gnd pins, and you re ready to start communicating via I2C. The default I2C address for the RangeWizard is 0x6E (110d). Please see Example Application section below for details on writing programs to communicate via I2C. 7

8 Power Supply When using the I2C port, the RangeWizard gets its 5V supply via the I2C port. For serial operation, there is a 5V regulator on board, so that it can be powered directly from a V battery. Please do not apply power to the external power port while the board is connected to the I2C bus. The differing voltages might conflict with each other, and cause undefined behavior. Make sure you don t swap polarity (Vcc and Gnd) when connecting the power supply! We do not warranty against such misuse. Figure 9 - External Power Supply Connection 8

9 Serial Protocol Details: All commands and parameters are separated by spaces. There are two types of parameters: Simple and Complex. Simple parameters are basically simple strings, such as hello or 1. Complex parameters are simple strings separated by colons :, such as hello:world or 2:1. Think of a complex parameter as a key:value pair. Complex parameters are used in commands where multiple ids are used in a single command. This allows multiple objects to be interrogated on the Serializer in a single atomic command. The number of required parameters depends on the command being issued. All commands (and associated parameters) are terminated by an ASCII carriage return character \r (0x0D), which is denoted by a <CR in the command set below. The <CR in the command examples below simply means that each command needs to have a \r appended to it before it will be processed. If you are using Hyperterm (or PuTTY) to send commands by hand, it simply means that you hit the return key. All responses will be appended with a <CR<LF, followed by a prompt string, which will signify that the RangeWizard has processed the command, and is ready to receive another command. If an error condition occurs, then a N<CR<LF followed by a prompt string will be returned. For commands which do not return a value, an <CR<LF followed by a prompt will be returned if the command was successfully executed. NOTE: The light grey portion of the command example below depicts the characters sent by the Serializer. command param1 param2<cr N<CR<LF Booting Up: Once the RangeWizard boots up, the following information is printed out (NOTE The example below is what you would see if you were using Hyperterm): RangeWizard, firmware v1.0.0 Copyright 2008, RoboticsConnection.com If you re not using Hyperterm, then this information isn t really useful. Thus remember to ignore this sequence the first time you read your serial port. We basically added it to aid in debugging communication troubles. If you do not see the information above appear during power up, the Baud Rate, Data Bits, Stop Bits, and/or Parity are probably not configured correctly on the host computer which is communicating w/ the Serializer. The RangeWizard ships communicating at baud, 8 data bits, 1 stop bit, No Parity, and no Flow Control. 9

10 Serial Software Configuration: By far the best Serial Communications application that you can use to communicate with the RangeWizard is PuTTY ( PuTTY is a free implementation of Telnet and SSH for Win32 and Unix platforms, along with an xterm terminal emulator. It is written and maintained primarily by Simon Tatham. To use Putty, all you have to do is download it, configure a couple of screens, and you ll be communicating with the RangeWizard! You can download PuTTY here: org.uk/~sgtatham/putty/download.html Once you open PuTTY, you will receive the following screen: Make sure you uncheck the checkbox that says Always ask before opening this file. 10

11 First, click on the Terminal category, and then under Line Discipline Options, select: 1. Local echo Force on 2. Local line editing Auto Next, you ll want to click on the Session category, and then: 1. Select Serial destination 2. Enter the COM port you will be communication over (COM11 in the example) 3. Enter the baud rate you will be using (19200 is the default for the RangeWizard) 4. Type RangeWizard in the Saved Sessions text box, and then click Save. 11

12 Now, simply click Open, and PuTTY will open in a terminal window. Make sure you have power applied to the RangeWizard, and hit return a couple of times. You should see a few Ns appear, followed by the serial command prompt from the RangeWizard. You can now invoke the RangeWizard serial commands at leisure, which are defined in the following section. Below we have used Putty to issue a fw, restore, and blink command to the RangeWizard. 12

13 Command Set Summary fw The fw command returns the current firmware version Example: fw<cr blink ledid:rate [ledid:rate] The blink command can blink one of the two onboard green LEDs simultaneously, or individually. Each complex parameter is comprised of an <ledid:blinkrate pair. The ledid specifies which of the two green LEDs to blink, and blinkrate specifies the delay between blinks. The minimum blink rate is 1, and the largest is 127. A value of 0 turns the led off. Each complex parameter must be separated by one or more spaces. Example 1: Blink LED 1 at a rate of 50: blink 1:50<CR Example 2: Blink LED 1 at a rate of 50, and LED 2 at a rate of 100: blink 1:50 2:100<CR Example 3: Turn off both LEDs: blink 1:0 2:0<CR cfg baud [baudrate] The cfg baud command configures the serial baud rate on the Serializer. Values can be 0=2400, 1=4800, 2=9600, 3=19200, 4=57600, or 5= You can also type in the actual baud rate string as well (e.g ). The default baud rate used to communicate with the Serializer is The cfg baud command without a parameter returns the value currently stored in EEPROM. Example: Set the baud rate of the Serializer to : cfg baud 5<CR Example: Set the baud rate of the Serializer to 19200: cfg baud 19200<CR 13

14 Example: Query value of baud rate stored in EEPROM: cfg baud<cr cfg units [unit type] The cfg units command sets the internal units used for sensor readings. Values are 0 for metric mode, 1 for English mode, and 2 for raw mode. In raw mode, readings are returned in units of 0.4us. The cfg units command without a parameter returns the value currently stored in EEPROM. Example 1: Set internal units to Metric system cfg units 0 Example 2: Set internal units to English system: cfg units 1 Example 3: Query internal unit configuration stored in EEPROM: cfg units 1 cfg mode [1 2] The cfg mode command sets the mode to read a one line (1) or two line (2) ultrasonic ranging sensor. A one line type of sensor uses a single line for trigger and echo functionality (e.g. Ping)))), A two line type of sensor uses two separate lines for trigger and echo functionality (e.g. MaxSonar EZ1). The default value is 2 (two line mode). The cfg mode command without a parameter returns the value currently stored in EEPROM. Example 1: Set the sensor mode to single line sensor: cfg mode 1 Example 2: Get the current sensor mode: cfg mode 1 14

15 analog The analog command returns the raw A/D (10 bit) reading for all analog sensor ports 0 5. NOTE: Readings for ALL ports are returned even if there isn t a sensor connected to it. Attempts to read an analog port value, which does not have a sensor connected to it, are considered invalid. Example: Read the value of the analog ports analog<cr delay This command sets the delay time, in milliseconds, between sonar readings (default = 25 msec). Example: Set reading delay to 35 milliseconds. delay 35<CR restore i2cp curraddr newaddr Restores the factory default settings, and resets the board. NOTE: This will erase any configurations you have saved to EEPROM, including baud rate settings. Example: restore<cr RangeWizard, firmware v1.0.0 Copyright , RoboticsConnection.com The i2cp command programs the I2C address for the RangeWizard from the current I2C address specified (curraddr) to the new I2C address specified (newaddr). NOTE: no other devices can be connected to the I2C port/bus while programming the address. Example: Change the device address from 110 to 115 (decimal). i2cp <CR 15

16 sonar [id] Query a specific ultrasonic sensor connected to the specified port. Values should be interpreted based on the value of the currently configured units. Example: sonar 4<CR 25 allsonar The allsonar command returns all ten sonar readings in a single response. Values should be interpreted based on the value of the currently configured units. The order of sonar readings returned ranges from 0 to 9. Example: allsonar<cr streams The streams command turns on a continuous stream of ten sonar readings per line (delimited by a CR/LF). The RangeWizard will continue streaming readings until a stop command is received. Values should be interpreted based on the value of the currently configured units. Example: streams<cr streama The streama command turns on a continuous stream of six analog readings per line (delimited by a CR/LF). The RangeWizard will continue streaming readings until a stop command is received. Example: streama<cr

17 streame The streame command turns on a continuous stream of ten sonar readings per line, followed by six analog readings per line (each delimited by a CR/LF). The RangeWizard will continue streaming readings until a stop command is received. Sonar values should be interpreted based on the value of the currently configured units. NOTE: Readings for ALL ports are returned even if there isn t a sensor connected to it. Attempts to read an analog port value, which does not have a sensor connected to it, are considered invalid. Example: streame<cr // Sonar Readings // Analog Readings stop Stops Sonar pinging and streaming. Example: stop<cr 17

18 I2C Protocol: The following table lists the various RangeWizard I2C commands. Commands should be sent based on the following byte sequence: <address <command [params] Command Description Notes 1 (0x01) Set number of control pins 1 for single pin, 2 for trigger & echo (default = 2) 2 (0x02) Start or Stop ranging 0 = Stop ranging, 1 = Start ranging 3 (0x03) Set reading delay milliseconds (default = 25msec) 4 (0x04) Set ranging mode to inches 5 (0x05) Set ranging mode to centimeters 6 (0x06) Set ranging mode to microseconds 7 (0x07) Request sonar sensor array [sonar1lowbyte, sonar1highbyte, Sonar10LowByte, sonar10highbyte] 20 bytes will be returned representing all 10 readings. 8 (0x08) Request analog sensor array [analog1lowbyte,analog1highbyte, analog5lowbyte, analog5highbyte] 12 bytes will be returned representing all 6 readings. 9 (0x09) Request sonar and analog sensor array [sonar1lowbyte, sonar1highbyte, Sonar10LowByte, sonar10highbyte, analog1lowbyte,analog1highbyte, analog5lowbyte, analog5highbyte] 10 (0x0A) Reset 32 bytes will be returned representing all 16 readings. 18

19 Communicating with the RangeWizard thru the Serializer WL Robot Controller via I2C: Communicating with the RangeWizard via the Serializer using the I2C bus and the Generic I2C command is very easy (assumes I2C address of 110 (0x6E). Remember that you re communicating w/ the Serializer serially, hence the Serializer command/response sequence below is similar to the RangeWizards serial protocol (defined above). The Serializer then communicates with the RangeWizard via the I2C bus. Set the number of control pins to 2: i2c w Set the delay between sonar pings to 20msec: i2c w Set ranging mode to inches: i2c w Start ranging the ultrasonic sensors connected to the RangeWizard: i2c w Query the ultrasonic sensor readings: (Note we have only one MaxSonar EZ1 connected to sonar pin 0) (Note that 20 bytes will be returned) i2c w i2c r Query the analog sensor readings: (Note we have only one GP2D120 connected to analog pin 0) (Note that 12 bytes will be returned) i2c w i2c r Query the ultrasonic and analog sensor readings (note 32 bytes will be returned 20 sonar bytes + 12 analog bytes): i2c w i2c r

20 Reset the RangeWizard: i2c w Electrical Specifications: Range Wizard Maximum Ratings DC Characteristics: Symbol Characteristic/Device Min Typ Max Units Conditions VDD Supply Voltage V IDD Supply Current ma Absolute Maximum Ratings Ambient temperature under bias: 55 to +125 C Storage temperature: 65 C to +150 C Voltage on any pin with respect to VSS: 0.3V to (VDD + 0.3V) Voltage on VDD with respect to VSS: 0.3 to +7.5V Total power dissipation on digital I/O pins: 1.0W Maximum current out of VSS pin: 300 ma Maximum current into VDD pin: 250 ma Input clamp current, IIK (VI < 0 or="" VI="" VDD): 20 ma Output clamp current, IOK (VO < 0 or="" VO="" VDD): 20 ma Maximum output current sunk by any I/O: 25 ma Maximum output current sourced by any I/O pin: 25 ma NOTICE: Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only and functional operation of the device at those or any other conditions above those indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability. 20

21 Dimensions: The Board is 2.2 X 2.75 x 0.5 inches (55mm x 70mm x 13mm) in size. 21