I assume this should be possible but I'm having difficulty so I thought I'd ask if it is, in fact, possible before continuing on. I have 2 digitrax decoders installed on two locos. They are both capable of 2 & 4 digit loco addressing. I use my Zephyr and a programming track to read back the default CV (03) and can change it to any other 2 digit address. I'd like to change it to a 4 digit address. This has to be possible, isn't it? Maybe I'm missing a step? Thanks.
You have to change CV 29 to value 38 for 4 digit addressing then you have to figure out the value for the 4 digit address. The easiest way for you to do this is download JMRI decoder pro and as you use the visual part to change what you want in the CV list it will tell you what CV to change to what value. Will save you a lot of time trying to figure out what CV does what and what the value should be. The even easier route is pick up a MS100 or similar computer interface and use Decoder pro to program your decoders without having to punch a bunch of numbers into the zephyr.
Ok, that makes sense that I'd have to tell the decoder to change to 4 digit addressing first. I assume I just change CV 29 to value 38, then READ the current value, then WRITE whatever value I want. I'll look into the JMRI decoder software and necessary hardware to connect to my pc. I only have 2 locos with decoders right now and would just like them to be addressed according to the numbers on the engine. Once I get that accomplished, I will probably begin playing with all the other variables at which point the JMRI software looks like a headache-saver. Thanks for the help.
When programming an address on the Zephyr, you hit "Prog" to select the programming mode, and then you hit "Loco" and the display shows "Ad2", and it is ready for you to enter a 2 digit address. If you hit "Loco" again, it will show "Ad4" and you can enter a 4 digit address and hit "CV WR", just as you would for a 2 digit address. The Zephyr will figure out the values and adjust CV 29 for you automatically.
I think that is what I was trying to do and it didn't seem to be working. I will try again and see if I was just impatient or missed a step. If that fails, I'll try changing the variable that determines the 2- or 4-digit address value.
It seems like I am getting the 4-digit address to the decoder on the locomotive...if I "read" the 4 digit address, it comes back as I programmed it. However, when I try to run it, it doesn't respond to the 4 digit address, it only responds if I use the two digit address. Any ideas? Thanks.
I'd make sure that CV29 is being set correctly. Even using my NCE system setting the 4 digit address and telling the decoder to USE the 4 digit address are two separate actions.
What addresses are you trying to program? If they are less than 128, that could be the problem. Digitrax will not let you select a 4 digit address below 128, but the Zephyr will let you program it. For example, if you have an engine number 123, the Zephyr will let you program it as a 2 digit address or a 4 digit address, but when you select 123, it selects the 2 digit address, so if you have it programmed as the 4 digit address, the enigine will not respond.
Thanks, this was the problem. It's not the most obvious thing in the world until you do it and then it's like, 'duh, that makes sense'. The decoders "knew" what their 4-digit address was after I programmed them but the base unit wasn't "speaking" in 4-digit addresses. Changing CV29 from the default value of 06 to 38 keeps the speed steps and forward/reverse direction the same but goes from 2-digit address to 4-digit address. The table in the manual (I know...RTFM) illustrates this pretty clearly. I suspect I would have come across this eventually but you'd think most people would want to do this first thing and it should probably be noted in the Starter manual where it shows you how to configure the address. Anyway, thanks for all the help.
That's odd that you would have to change CV29 manually because the Zephyr is supposed to do that for you - that is why it is not pointed out in the starter manual. I am using a Zephyr and when programming decoders I can go back and forth between programming 2 digit and 4 digit addresses and I have never had to change CV29 manually.
All I know is that I followed the manual to program the 4-digit loco address into the decoder. Then I would 'read' it back and it was correct. When I put the loco on the operating track it would only respond to the 2-digit address. When I manually changed the CV29 it would talk to the 4-digit addressed locos. That begs the question though...can it talk to both 2-digit and 4-digit locos at the same time???
The base unit doesn't "speak" in one address format or another, it is multi-lingual. If you select a 2 digit loco, it will run that, and if you select a 4 digit loco, it will run that one too. The address format is determined by CV settings in each decoder. Both formats can be intermixed freely on a layout. 2 digit addresses (0-127) are stored in the decoder as CV1, 4 digit addresses (128-9983) are stored in CVs 17 & 18. Which one the loco responds to is determined by bit 5 in CV29 (bit 5 has a decimal value of 32, so a setting of 38 will enable the loco to respond to it's 4 digit address, while a setting of 06 will enable 2 digit addressing). When programming "Ad2" or "Ad4", the Zephyr will automatically set CV29 (actually bit 5 of CV29) for the appropriate address format, however unless you try to MU two locos together, it will not mess with the decoder's CV19. What is CV 19 you ask?? It' is the Advanced Consist address. Any loco with a non-zero value in CV19 will respond to that value as a 2 digit address, irrespective of what the CV1 or CV17/18 addresses are, or what the setting of CV29 is. This is typically done when MUing two or more locos together by programming a common consist address for all of them. You may have inadvertantly set CV19 to have the same value as CV1 (by mistakenly trying to MU this loco with another one, for example, causing the Zephyr to set CV19 accordingly). If this happened, you might think the loco is responding to its 2 digit address (CV1), when in reality it is responding to it's advanced consist address (CV19). Setting CV19 to "00" will clear this and allow the loco to respond to the appropriate 2 or 4 digit address per the CV29 setting. HTH
That does help and I suspect you are correct in that I probably set CV19 while trying to program the decoders. Thanks for the clarification...it's starting to make some sense to me.
You did say earlier that manually programming CV29 enabled the 4 digit address. It just ocurred to me that this would not work if CV19 were other than 00. Hmmmmmm.......
I'll have to look into how or if it's possible but maybe I should try to reset the whole system and start from scratch. Maybe some CV's are not at their default value's and that is causing some confusion. This was a used system so that could probably explain it.
Would it work as a 4 digit if you entered 0123? Or would it still only respond to it's 2 digit address?
If you program the enigne with the 4 digit address of 0123, then no it won't work if you try to select 0123(assuming we are still talking about Digitrax here). In fact, if you press "loco", then "0", "1" , "2", "3", the "0" will dissappear, showing you that the address you are about to select is the 2 digit address "123"(I'll explain later how you can have a 2 digit address with 3 digits). If the loco is set for 4 digit addressing, it also will not respond to it's 2 digit address. CV29 controls whether the loco will respond to it's 2 digit address or it's 4 digit address. When it is set to respond to its 4 digit address, it will not repond to its 2 digit address and vice versa. I would also like to point out something here. "2 digit address" and "4 digit address" really is not the correct terminology, it should be "short address" and "long address", that is why you can have a "2 digit" address with 3 digits. A short address can be any number from 1 to 127. Some of the early DCC systems that only used short addresses limited them to two digits so that they would not have to use a display that could show three digits, and systems that used long addresses were advertised as having 4 digit addressing, and I think that is why the 2 digit and 4 digit terminology become popular.
Augy, One more thing. If you feel like you did something wrong and you are not sure what to do next, program 008 into CV 08, it will reset the decoder to factory defaults. You can start over from the beginning without worrying what is in what CV. Greg
