Serial connection Omron CQM1 to Syswin?

[Guest Beaglaoich]

Hi, I have recently acquired an Omron sysmac CQM1 (CPU21) PLC with a copy of syswin 3.3; with this I intend to learn PLC programming. I would like some help in connecting up this PLC to my PC. I’ve tried unsuccessfully to connect to my PC using an RS232 cable. My cable pin out is PLC To PC; 2 - 2, 3 - 3, 9 – 5, PLC side 4 connected to 5, PC side 4 connected to 6 and 7 connected to 8. My dip switch settings on the PLC are 3 & 4 on (message English and default instruction set) all else off. I’ve tried different serial communication settings in Syswin to no avail This novice would appreciate any help/advice offered. Thanks, Tom

[Jay Anthony 118]

Your cable seems to be correct. Turn dip switch 5 on to force the comm parameters to be 9600, E,7,2 and set the Syswin parameters to be the same. Tell us what Syswin has to say about it. Also tell us what the lot code is on the CPU. You will find it on the label on the side of the CPU. This may make a difference.

[Guest Beaglaoich]

Hi Jay, Thanks for your reply. I did as you suggested, turned on Dip sw 5. The response syswin gives is the same ‘No response from the PLC’ On Syswin PLC set-up I’ve checked the default 9600, 7, E, 2 The led COM2 on the front of the PLC flickers when I try to connect both with sw 5 on and when its off. The Lot no for the CPU unit is 2976. I forgot to mention also that I am using pin 1 as ground. Though my copy of syswin is 3.3 my Dongle is v3.2a, however it indicates on starting that its fully activated? Regards, Tom

[Jay Anthony 118]

Any Syswin Dongle will fully activate any version. Do yuu have any other software running at the same time which will grab the PC serial port? Hot Sync? Modem Sodtware?

[IO_Rack 181]

Jay.... you know way too much about Omron products. Sorry for the interruption.

[Jay Anthony 118]

You wouldn't believe the Omron trivia I've forgotten.

[Guest Beaglaoich]

Hi Jay, Problem resolved! This morning I made up a new cable and though the original cable checked out for continuity I had not connected pin 1 to pin one and on to the cable shield! Many thanks Jay for directing me, with your help I was able to review my original cable configuration. Hopefully my next query will be more challenging for us both! Cheers, Tom