BX-DMIO Error Slot 255

[JeffS]

I have a remote IO module reporting a configuration mismatch on Slot 255.  I tried re-writing booter/firmware, reset defaults, rewrote booter/firmware to the BRX Master with no luck.  I am assuming this remote IO module is dead, but wanted to report the odd message.

[JeffS]

So the customer replaced the BX-DMIO and it is still showing an error light on the DMIO and when I log into the BRX PLC I see the same Slot 255 error. 

So at this point I guess the BRX Master is the bad component here, just very misleading as the error points toward the DMIO device?

[BobO]

So the customer replaced the BX-DMIO and it is still showing an error light on the DMIO and when I log into the BRX PLC I see the same Slot 255 error. 

So at this point I guess the BRX Master is the bad component here, just very misleading as the error points toward the DMIO device?

Slot 255 actually points to the onboard I/O, which there isn't any. It isn't a hardware problem, it's probably garbage in the config. I've been out on vacation, but I'll look into it when I'm back in the office.

[JeffS]

So I sent them a new PLC and they got the same error.  I had them factory reset the PLC (Dips and RUN/TERM/STOP dance) and I remotely reloaded the program and got the same error.   I am only getting this error at this one site luckily, but so far not able to rectify it.  This setup ran fine last year and nothing has changed on the system (no changed code/sensors/wiring).  They were running 2.9.6 firmware so I did update to 2.10.3 but the error persists.

So at this point we replaced the BX-DMIO and the BX-DM1E-M-D, initially restored the new PLC from a backup of the old PLC, then since the problem persisted, factory reset that PLC using run/stop dance, reloaded from a clean copy, and the problem persists.

Any thoughts on what to check next?

[BobO]

I've been communicating with JeffS off the forum, but to complete the public record, we found a bug in the Ethernet Master where in certain conditions (rare, I think), the master sent a malformed request that resulted in this symptom. The fix will be in the next OS to be released shortly.