I've been looking around at some DCC systems (Hornby Elite, Bachmann Dynamis and NCE PowerCab), and I've come across the idea of CV readback. If I've understood correctly, this is the ability to read the current settings of the decoder. So, my questions are: 1) Is there more to readback than that? Or have I got it right? 2) Is the ability to readback a function of the controller or the decoder? Or both? 3) Do I really need it in a relatively simple layout? (no details as yet, but likely to be no more than half a dozen locos present on the layout, with probably only a couple running at a time) Thanks, Dave.
1) You have it right. 2) Both. 3) Probably not. My Digitrax system will not readback MRC sound decoders (as in the Athearn Challenger) without a booster, but I muddle through. Ben
It is definitely a "nice to have" rather than a "must have". If you choose the same Digitrax system as Ben (above - I think he's got the "middle one" but the name escapes me) you can always use something like Decoder Pro with an old computer to do the read=back (and programming) of your decoders. Andrew
CV readback is a "nice to have" when everything works, but when you get wierd rsults or things aren't working right, it rapidly becomes a "must have". I have an Empire Bjuilder (DB150) which, among its many "features" is the inability to read back CVs. Decoder Pro and LocoBuffer won't help, as the issue is in the command station. I bought a Zephyr for readback (among other things) and all is now right with the world (or at least my little version of it).
Doug... Are you saying that a computer running the JMRI software (Decoder Pro??) cannot read CV's on a programming track? I thought this set-up was independent of a command station? Maybe my misunderstanding...? Andrew
Hey all . Thanks for the replies, it's been very helpful. I guess I won't worry too much about it . Dave.
If the command station does not support reading CV's, then adding the JMRI software will not add that support. In my opinion, CV readback is most useful if you are doing complex lighting functions or custom speed curves. If you don't get the results you expected, it is nice to be able to read the CV's to make sure they are what you think they are.
Readback is in mine humble opinion a must have option. Without you have always to record the settings on a piece of paper (which I always can't find when I need it). This is also the reason why I switched from a Roco Mulimaus system to a Lenz Set-100 Gino
As stated by others, if the command station can read CVs, JMRI (which operates through the command station) can read them as well. The Empire Builder DB150 command station cannot read CVs, so JMRI, while great for programming, still will not be able to read back. (BTW, note that the DB150 does not have a "programming track" per se, it just uses the main track as a programming track when needed). Your original question was if CV readback is really necessary. I think you've figured out that No, it's not absolutely necessary, but like A/C in your car, it is highly desireable.
Old old post, but I did a search and this is the right one. Can the NCE PowerCab do CV readback? I ask because I just got one (!) and can't figure out how to get the handheld to display the values. The chart at Litchfield Station indicated that it can Read & Write CVs. Edit: Duh, nevermind. I figured it out.
