USB POMs Failing

[Mike Nash]

I have 2 useless-to-me USB POMs on my desk right now. The first failed sometime last year I think. The second one was just this morning after it successfully upgraded a brand-new-from-the-box BX-DM1-10AR-D from 2.0 to 2.3.

The computer makes its USB connect disconnect sounds. The link can be configured in DMD. It knows what type PLC it is. It can flash the Err LED. But I get a timeout when connecting.

I am afraid to plug in the last unopened POM on hand. The last one to fail has never been hot-swapped. The first one that failed has never been able to connect on any model I tried afterwards. I don't recall if it was after a firmware update on the first one. Yes, I have the very latest versions firmware and software (but the Check for Updates in Help is broken this morning for any version I try.)

Either of the BX processors can connect via RS-232 and the DM1E connects with ethernet.

[Mike Nash]

Further wasted time on this project (sorry, but this is an issue that has been reported before on ADC forum) shows that I can get either POM to work again by doing the 11-11 reset in the manual. Then I am good right up until I disconnect, either via the PLC-Disconnect selection, or closing the DMD software. Then it fails to connect again, suggesting it might be old PLC firmware or simply a timeout, and only timeout is shown.

It can't be my program, because I don't even have to put a program in. When I select Disconnect it wants to save, so I give it a filename and save, it wants to save to the PLC, so I let it. Try to connect again, no-go.

[BobO]

If we can dupe it, we'll fix it. Unfortunately we haven't been able to dupe it.

If clearing the system fixes it, then it clearly isn't a hardware failure, so that's good.

Any expansion I/O, or just the brick?

[Mike Nash]

Just the brick. No I/O wires have been attached. Pulling the USB cable out of the POM while it is connected that first connection after resetting to factory, times out, but after plugging it back in, it will recover the connection after a reasonable time.

I have no idea whether the whole act of updating the firmware causes any of this. The BX-DM1E-36 I have is an early model that is currently at v2.2.1 while this 10 pointer came in Monday from ADC with v2.0.x something in it and I nearly immediately updated due to needing a new feature or something. The ladder was not doing anything funky though and no ladder at all gives the same problem.

[BobO]

And is the behavior the same across different PCs? Have you tried different USB ports on a PC that fails?

Writing to the PLC will cause more data to be read the next time you connect. If the USB connection is marginal (for whatever reason) it would be more likely to fail after you've written to it.

[Mike Nash]

Rats! Windows XP has another nail in the coffin.

XP SP2 Desktop   Fails on 2nd try
XP SP3 Laptop    Fails also
XP SP3 in Virtual Machine with Win10 Host Fails too
Win7 Pro 64bit in VM with same Win10 Host Works fine, both POMs and both PLCs

So three physically different XP machines all fail.

Thanks for looking and maybe we need an explicit warning on this. Yes I know XP is not supported anymore, but everything else has worked so far. Unsupported also means Microsoft is no longer reaching out and screwing everything up. (Anyone else get a Lucky You! from MS?)