I just installed an MRC 1803 board replacement decoder in an old LL PA. Loco ran fine before switchout, but now it will not read back from MRC Prodigy Wireless Programing track nor will it re-program. DCC system is working fine as programing and read back still respond for other locomotives.
Now for the strange part. On my DC test track everything works great. I get sound, acc and dec momentum, and overall great speed response. If the decoder were blown, I'd expect a short out or total non-response. Any ideas.
I'd like feedback that does not simply trash MRC decoders and stop there. Read waaaay too much of that on this discussion site. It may very well be another crapped out MRC decoder, but the board is working enough to fully operate the locomotive. My limited experience with blown decoders is that they create internal shorts that shuts everything down.
I've not gone to the layout yet, but that is the next step unless someone has a better idea. Worst thing that could happen is the board would totally fry and at this point I'd at least know what's going on.
Mike
You seem to be saying the loco runs OK but the decoder does not read back. Is that right. The MRCs generally don't read back CVs, but I have a couple that do.
I've had a much similar looking problem with an MRC sound decoder...it would go fine on DC but was dead on DCC.Short of ideas,I rewrote CVs 1,2,5,17,18 and 29 with the factory default datas and the loco came back to life.I couldn't read them (like you) so reprogrammed them blind.I can only assume that one of these CVs was messed up.These MRC decoders have a tendency to lose their memory here and then.
Forgot to say,my loco wouldn't reprogram on the prog. track either but did reprogram fine on the main in OPS mode.I have a Digitrax system,may be different for you.
They tend to not read back anyway, at least not reliably. I had a club member want to change volume on a decoder and he didn't know what was in it so I attempted to ID it with JMRI, and I discovered that my PR3 program track could read it, but only one or two CVs at a time, which finally got the manufacturer ID as MRC and then I was able to bit by bit read the information from it, but any attempt to do anything more complex liek read a full page in JMRI just resulted in a timeout. The loco operated just fine despite this, so the no or poor readback isn't necessarily a sign of a failed decoder, it's just the way they are. If blind writes are actually making changes on the program track, and it runs on DC, it's not likely shorted out in a way that would destroy it if placed on the DCC main.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Thanks, guys for the helpful responses. Taking them all into account, plus a helpful analysis from Frank at MRC tech support, I decided to go ahead and try it on the layout. Here's what happened:
1. One final attempt to get readback on the program track--No luck.
2. Put it on the layout and called up address 3----Success with all functions and sounds except the lights (I'm going to work on that later.)
3. Back to program track to set a new 3 digit address. No readback, but.....success on the layout!!
Conclusion: Can program on the program track, but like a couple of you said, it is a a hit/miss process. More work, but I'll learn in the process. Too many DCC locomotives on the layout to try programing on the main just yet, but if I can keep doing it on the p-track, that's fine with me.
Thanks again.