RS232 Serial Interface (Option)

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P8721RS232 RS232 Serial Interface (Option) ELEKTRO-TRADING sp. Z o.o. 44-109 Gliwice, ul.

1 P8721RS232 RS232 Serial Interface (Option) ELEKTRO-TRADING sp. Z o.o Gliwice, ul. Mechaników 9 tel (032) , fax. (032) poczta : et@elektro-trading.com.pl P8721.SN000.SV001.V2-3.PID(E) 51/98

2 1 General 2 2 Technical information 2 3 Data format 2 4 Activating the Serial Interface 2 5. Rules of communication 3 6. Emulator 3 7. OPERATING DETAILS Checking communication Changing the operating Mode Read the actual count value Set the Counter to a value Read the displayed position Single Mode Program Mode Auxiliary Outputs STS Program End Point Starting from a Decided Program Address Positioning Register Control Error Codes Summary of protocol Errors Hints for Secure data transmission Communication Errors 11 2

3 RS232 SERIAL INTERFACE OPTION 1. GENERAL The P8721 Position Controller can be fitted to order with RS232 serial interface. This enables the unit to be controlled remotely from a PC or PLC. This requires additional hardware and software inside the P8721 controller. Using the serial interface it is possible to effect the following. - Check communication - Change the operating mode - Read the actual count value - Set the count value - Read the displayed position - Read the demand position - Write the demand position - Read a program - Start the controller - Stop the controller - Reset the controller - Read a register - Write a register 2. TECHNICAL INFORMATION The connections for the serial interface are on a 3 way round connector. Pin Designation 3 Data out (TX) 2 Data in (RX) 1 Ov 3 Data Format The data format is: 9600 baud 8 Data bits 1 Startbit 1 Stopbit no parity 4 Activating the Serial Interface The serial interface is enabled by setting Register R18/1 to 1, inside the P

4 5. Rules of communication All characters are udper case ASCII. All lines are terminated with carriage return (13 decimal). Character spacing must be a minimum of 5 ms spacing. All position data is in Encoder bits. 6. Emulator To assist customers in the task of integrating the P8721, an Emulator Pack option is available. This comprises operating software on a 3.5" disc plus 2m cahle with 'D' connectors fitted. This will enable the customer to instantly run the 87P from a PC and then prepare his own prograinme, incorporating the required instructions. This software runs on any IBM PC XT or AT compatible running MSDOS 3.2 or higher. 7. OPERATING DETAILS 7.1 Checking communication Send A (CR) 651 L 13 87P@Ready ******(CR) 7.2 Changing the operating Mode It is pcssible to switch the operating mode from single to program and vice versa. To switch to single mode Send M S (CR) To switch to program mode Send M P (CR) Before a mode is changed it is recommended that RE (CR) is sent to reset the controller. 4

5 7.3 Read the actual count value Send R A X (CR) (CR) This value is the actual value of the P8721's internal counter, irrespective of the multiplier setting (Register 91). 7.4 Set the Counter to a value Send : W A X : (CR) This sets the 87P's internal counter, irrespective of the multiple setting (Register 91). 7.5 Read the displayed position. Send R D X (CR) (CR) This value is the displayed position of the controller taking the multiplier into account, Register 91, and the tolerance window Register Single Mode In this mode the demand position can be transmitted and read. For example if a demand of 1000 is required Send PX : (CR) This position will now appear in the demand window on the 87P. To read the demand position Send : RRX(CR) (CR) 5

6 7.7 Program Mode In this mode the program can be written and read. To write a line of program the following could be sent P N W : 0 1 : : : 1 : 02 (CR) Address Demand QUANT Auxiliary Number 1 Position Outputs To read a line of program, send P N R : 0 1 (CR) Adress Number 0 1 : : : 1 : 01 (CR) Number Position quant code outputs If the 87P is being used in reduced field mode, then ignore all fields which are not used. 7.8 Auxiliary Outputs STS Using the keypad allows only one auxiliary output at a time to be programmed. Hawever, using the serial link it is possible to have any or all of the outputs. This is achieved by sending the character "Hll followed by the hexadecimal coding for the required output combination (see auxiliary output table). Example 1 PNW : 01 : : 010 : 1 : 02 If a zero is sent, the following character is treated as would be an input from the keyboard. ie 0-4 and only one output will be on per line of program. Exammle 2 PNW : 01 : : 010 : 1 : H8 If a "H" is sent the next character is treated as a hexadecimal value and the output combination is as the Auxiliary output table. 6

7 Auxiliary Output Table Coding ST5 Auxiliary Outputs A B c D E F Program End Point To set the program end point it is necessary to send the last program number required in the following format PEW : 03 (CR) Program end to be at address 3 To read the set program end point, send P E R 0 3 (CR) 7.10 Starting from a Decided Program Address It is possible to set a number of program lines within the P8721 and call by the computer, the required address. Example To start positioning at address 03 Send NR : O 3 (CR) Adress The address 03 will now be displayed. 7

8 Issuing "start" will begin positioning to address Positioning To start positioning send S A (CR) While positioning is taking place, serial communicati(dn is possible. When position has been reached the 87P will send. P R X (CR) When a program end is reached the 87P will residond with DONE (CR) To stop positioning send : ST (CR) STOP (CR). The controller can be reset by sending RE (CR) STOP (CR) If during positioning the "Stop" input is activated the 87P will send STOP (CR) During positioning the following commands are allowed RAX (CR) - read the actual value of the counter. RDX (CR) - read the displayed position RRX (CR) - read the required position, in Single Mode onl@7. ST RE - Stop Positionina - Stop positioning, reset the controller 8

9 7.12 Register Control To write a register, send : PRW : 05 : (CR) 1 1 Register value Number To read a Register send PRR : 05 (CR) Register Number 05 : (CR) The security code is NOT required when writing to registers via the serial link Error Codes The 87P will respond to error conditions with the following ERROR 01 (CR) ERROR 02 (CR) ERROR 03 (CR) STOP (CR) - Communication failure - A move was attempted which is beyond a software limit - An encoder not counting error has occurred - The stop invut was activated 9

10 7.14 Summary of protocol A - Check 87P is on line MS - Change to Single mode MP - Change to program Mode RAX - Read the actual count value WAX : 12345,6 Set the counter to a value RDX - Read the displayed position RRX - Read demand position (Single mode onlv) PX Write demand Position (Single mode only) PNW : 01 : : 123 : 1 : 01 - Write a line of program PNR : 01 - Read line 1 of program PRR : 91 - Read register 91 PRW : 91 : Write to register 91 PER - Read program e.id point PEW : 05 - Write program end point at address 5 SA - Start positioning ST - Stop positioning RE - Reset controller 7.15 Errors STOP ERROR 01 ERROR 02 ERROR 03 c - Stop input was activated - Communication error detected (Framing or overflow) - Move attempted which is heyond software limit - Encoder not counting error detected - Flushes 87P's serial input buffer Backspace (decimal 08) - Will move the 87P input buf'fer pointer back by 1 character Smace (decimal 32) - Ignored 7.16 Hints for Secure data transmission In order to ensure that transmitted data is receved error free, it is recommended that the following procedure is used. 1. Transmit data string. 2. Read data back 'arom 87P. 3. Check that received and transmitted data a@e identical. 4. If not, read data back again. 5. Check that received and transmitted data are identical. 6. If not, restart from point 1. 10

11 7.17 Communication Errors If at any time during communication an "Error 01" is received this indicates that the 87P has received a data byte incorrectly. The following procedure must now be performed by the host. 1. Stop transmission 2. Send "CR" 3. Resend whole data sentence. 11

Doug Fleenor Design, Inc. RS-232 to DMX512 Interface, 2 Generation. March 8, 2010 (Software V1.2)

Doug Fleenor Design, Inc. RS-232 to DMX512 Interface, 2 Generation. March 8, 2010 (Software V1.2) Doug Fleenor Design, Inc. nd RS-232 to DMX512 Interface, 2 Generation March 8, 2010 (Software V1.2) The second generation RS-232 to DMX512 interface has numerous features beyond the original device. The