Errors that appears when i connect via serial port

[Msobh]

Hello,

I have PLC Omron CJ1M/CPU11, the problem is whenever i connect the PLC to my PC (laptop) via serial port and try to go direct online using cx-programmer either it fails to upload or the following errors occurs

 

https://42cdn.com/b2api/v1/b2_download_file_by_id?fileId=4_z6177fca890d8c37157cc0814_f109c6c5bb1ff3a05_d20180416_m205233_c001_v0001042_t0043

 

These errors only appear when the machine start working when the machine stops the errors disappear, this happens only when i connect via serial port. I tried connecting via peripheral port, no errors appeared which is kinda weird.

I tried changing the cable, it didnt work. Any help ?


Thanks in advance and have a nice day.

Edited April 16, 2018 by Msobh

[BITS N BYTES]

What is the pinout of the Serial Cable you are using? Looks like it may be incorrect and is shorting out the serial port and subsequently faulting the PLC.

Edited April 17, 2018 by BITS N BYTES
Add cable pinout

[Msobh]

On 4/17/2018 at 1:28 PM, BITS N BYTES said:

What is the pinout of the Serial Cable you are using? Looks like it may be incorrect and is shorting out the serial port and subsequently faulting the PLC.

Hello,

Thanks for your reply, the pinout of the cable i am using is the same one as you have shown. The cable also works with other PLCS, which is really confusing.

[BITS N BYTES]

Hmmm! What are your Serial Port settings? They should look something like attachment. Remember to "Transfer to PLC" AND MOST IMPORTANTLY POWER CYCLE THE PLC for the new settings to take effect AND set DIPSWITCH 5 to OFF.

[Msobh]

On 4/18/2018 at 8:09 PM, BITS N BYTES said:

Hmmm! What are your Serial Port settings? They should look something like attachment. Remember to "Transfer to PLC" AND MOST IMPORTANTLY POWER CYCLE THE PLC for the new settings to take effect AND set DIPSWITCH 5 to OFF.

Hello,
Thank you so much sir, That actually worked and the errors disappeared. I really appreciate it. But if I may ask, would you ( if you have time of course) explain to me what was that problem ? was the data transfer rate from the PLC to the PC slow so it resulted in some kind of communication error ?

Again, Thank you sir. I really appreciate it.
Have a good day.

[BITS N BYTES]

Glad to help.

My best guess is that with dipswitch 5 ON the default setting of the Serial comm. port is HostLink, 9600 Baud, 1,7,2,E but CX-Programmer by default uses Toolbus at 115200 Baud, 1,7,2,E.

This conflict possibly caused the Sync/Async Communications in the Peripheral Service to take too long to execute and faulted the PLC.

If anyone else has a better reason please chime in.

[Michael Walsh]

My first thought is some kind of grounding / potential issue on the computer's comm port. or there could be some kind of ground issues with the PLC.  That is what I would check.  Settings and dip switch settings would not cause the errors that you are seeing.  

[Msobh]

2 hours ago, BITS N BYTES said:

Glad to help.

My best guess is that with dipswitch 5 ON the default setting of the Serial comm. port is HostLink, 9600 Baud, 1,7,2,E but CX-Programmer by default uses Toolbus at 115200 Baud, 1,7,2,E.

This conflict possibly caused the Sync/Async Communications in the Peripheral Service to take too long to execute and faulted the PLC.

If anyone else has a better reason please chime in.

Well, when i checked the dipswitch it was already off,  The default serial port setting was as attached, I changed the settings as you said. At first it did some uploading errors, but then it worked and the errors disappeared. But now I have noticed that the PLC is talking longer to connect and alot of times it fails to upload. But when it uploads and works everything works great, and no errors appear. It is just confusing you see.

Thank you again for your time and help sir.

Edited April 19, 2018 by Msobh

[Msobh]

51 minutes ago, Michael Walsh said:

My first thought is some kind of grounding / potential issue on the computer's comm port. or there could be some kind of ground issues with the PLC.  That is what I would check.  Settings and dip switch settings would not cause the errors that you are seeing.  

Hello Mr Michael,
I Will Check if there's some kind of problem with the grounding.

Thank you for you time and help sir.

[Michael Walsh]

14 hours ago, Msobh said:

Well, when i checked the dipswitch it was already off,  The default serial port setting was as attached, I changed the settings as you said. At first it did some uploading errors, but then it worked and the errors disappeared. But now I have noticed that the PLC is talking longer to connect and alot of times it fails to upload. But when it uploads and works everything works great, and no errors appear. It is just confusing you see.

Thank you again for your time and help sir.

 

Wow, I am surprised.....must not really be getting those errors on the processor, just an incorrect notification.