EUID Decode Errors

[tharron]

I just corrected another minor issue with the response packet for DISC_MUTE and I think my device is now relaying valid response packets for the mute command; however, looking at the packet history I'm not sure what the DMXter is doing.

I manually set up the UID and then sent a MUTE packet via the DMXter. I can tell the light identifies(why?), but the DMXter reports WRONG PDL FOR PID. If I click the Yes button again I see the destination UID as well as NOT RESPONDING.

After this I went and checked the packet history, and the first thing I see is a good response from the mute packet. Above that is a broadcast identify packet, a device model description packet, an identify packet response (I think this is the response packet the "wrong" PDL) and finally another broadcast identify device.

"EUID Decode Error" means the DMXter's RDM controller saw activity on the wire during the Discovery Response Period, but that it could not find a valid EUID in the data. It could be that the checksum does not match or some similar issue.

Please confirm that an invalid checksum could cause the decode error? I have double- (and triple- and quadruple- and...) checked my checksum code, but while I am fairly confident it's OK I'm even more confident about the encoding of the UID.

A common problem is the responder turning off the 485 line driver's transmit enable signal before the last byte has been fully sent. You need to make sure that all 8 bits have been shifted out along with the stop bits before turning off the transmitter.

I was actually running into this problem previously, but I noticed it pretty quickly and it looks like everything is making it out of the transmitter before I disable it.