Omron Fatal Error after converting program from a C28H to CPM2A

Join Date
Mar 2003
Help! I'm not too familiar with Omron.
I would like to know if there is an easy way to locate where the problem is in the program?
I converted an existing working program from a Omron C28H plc to a new CPM2A plc.
I had to relocate some addressing because of different memory ranges to eliminate the errors I was getting in the Program Check feature in the syswin software, all of those errors are gone now. But after downloading the program, I have a memory error described as follows: (There is a non-existent bit or word address in the user program.)

How do I find the problem?

Thank you

If the program is fairly small, try splitting it in half and then downloading to the PLC. Keep splitting the program to narrow it down.
I know this is a crude way and that specific methods exist but I have to troubleshoot many different brands of PLC's and I'm not that proficient on Omron. Perhaps Jay Anthony at could help.
Syswin error should include reference to line number, which may help debuging.
Different Omron PLC families has different addresses for control/system variables (such as sytem timer accessible by user program). You can get the address reference index for your program and check which one(s) are not in CPM2A address space.
My proficiency is limited to the CPM1 & 2 family and C200H family, so I do not have the C28 manual to compare.

Whish you luck and success debuging your program.
Short of checcking all the I/O numbers against the CPM2A address allocations, there is no simple way. If you e-mail me the programme I will have a look at it for you.
What version of Syswin are you using? Hopefully 3.4.
The C28H internal memory map is identical to the C200H internal memory map. When the CPM2A internal memory map is compared to the C28H internal memory map, large gaps in the CPM2A map appear in the IR, AR,HR, LR and TC areas:

The IR area runs from 000 to 049 and from 200 to 255. The area from 050 to 199 does not exist.

The AR area runs from AR00 to AR23. The area from AR24 to AR27 does not exist.

The HR Area runs from HR00 to HR19. The area from HR20 to HR99 does not exist.

The LR area runs from LR00 to LR15. The area from LR16 to LR63 does not exist.

The TC Area runs from TC00 to TC255. The area from TC256 to TC511 does not exist.

If you are checking his program, be sure to check for addresses in the above non-existent areas.

cpm2a memory map.jpg
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