Omron PMCR CX Protocol Help

[Mad Bents 0]

My project that I am trying to complete is to use a Starrett digital contact style indicator gauge to send data to a Omron CJ1G CPU-42H using an SCU21-V1 (version1.3) serial communications card using PMCR instruction. This is not the first time I have done this type of project, however it has been a while since I have done something similar but with a Mahr Federal indicator gauge. I have determined that the Starrett gauge which is connected to a Multiplexer that only 4 wires (Pwr, Gnd, CTS, TXD) are used to transfer data when mux/gauge is connected to a "windows PC" using Terminalv1.9b software to communicate. "Note-Gauge sends data continuously once data button on gauge is pressed". However, when I connect to the omron PLC SCU port#1 I have yet to see data from gauge to be displayed in the data memory associated with the PMCR instruction, however if I open CX-Protocol I can perfom a trace and see a chart consisting of what looks like receive of hex data. I do not understand trace or know how to use it as a tool. A little help here is needed. Also I need someone to help me confirm the cx-protocol macro that I wrote to see if it is correct in seeing data. Gage data seen in windows PC Terminalv1.9b software looks like: "040,  +0.6576, NRM, 01" which is in Full comma-delimited format (NNN, SRRRRRRRRR, SMMM, SCC<CR><LF>) NNN-Reading Number, RRRRRRRRR-GAGE READING, MMM-MODE(MIN, MAX, TIR, NRM), S-SPACE, CC-Channel Number . My cx-protocol macro for receiving gage data is: (W(1),3)+","+&(W(2),2)+"."+&~(W(3),4)+","+(W(5),3)+","+(W(6),2)+CR+LF . The gauge sends data using communication protocol parameters: 9600-Baud , Parity-None, Bits-8, Stop Bit-1. My current wiring from "Starrett gauge multiplexer to Omron SCU21 Port#1" is: #2(TXD) MUX to #3(REC) Omron SCU, #9(PWR 8.6vdc) MUX to #8(DTR) Omron SCU, #5(GND) MUX to #9(Common) Omron SCU, #7(CTS) MUX to #4(RTS) Omron SCU. Please also someone confirm my wiring here. Any help with this is very much appreciated. 

[tashinz 9]

I would guess that whole response from your gauge is either hex or ascii (my bet is ascii) you you should frame your cx-protocol like that ($ for ascii & for HEX) or you should keep it only like variable (without $ or &) and put it something like W(DM100, 20), this 20 being 20 bytes, but i think it can be more just to be sure you are getting whole message. Then you analyze it in ladder and do required conversions in order to get usefull informations.

regards

[Jay Anthony 117]

Good call! Tashinz