Bachmann decoders not responding to Digitrax controller

[kevin2083]

I recently bought a Digitrax Zephyr DCC controller and have been trying to configure the CV's on the Bachmann decoders with no luck. I can't even change the addresses. I've had no problems with MRC and Digitrax decoders, but the two from Bachmann aren't cooperating. All I get on the display is a "d Nd" or "d NA". If it helps these decoders are from a 70 tonner and a GP40.

Also, would the CV tables from the 1-amp decoders be the same for these two?

Kevin

[r0bert]

you need to add a 1000 ohm resistor across the program track rails, then the Zephyr will read the lenz based, and sound decoders.

[kevin2083]

Thanks, that worked. I also awnsered my own question about the CV tables.

Kevin

[scott V.]

robert, 
Will the 1000 ohm resistor on the programming track also work with a pr3?
My pr3 will write cv's fine but has a hard time reading the bachmann decoders.

Thanks

[Jim Banner]

scott, I don't know if it will help, but it certainly won't hurt either the PR3 or the decoder to try it.  Please let us know what you find.

[scott V.]

I tried the 1000 ohm resistor on my programming track with the pr3 and it didn't make any difference.  I used JMRI and also tried the soundloader software on 3 different engines with bachmann decoders.  It would write to them but not read.   I'm going to change them out for digitrax decoders.

Scott

[rustyrails]

The Zephyr has several programming modes.  If you are trying to program in OPS mode, the decoder must be an Extended Packet Format type.  I haven't been able to find out if the Bachmann decoders are Extended Packet Format or not.  But....the Zephyr certainly should be able to program any decoder in paged mode (Digitrax says that's their favorite way) on the programming track.  If you can't somebody should lose their NMRA warrant.  LOL
Rusty

[Jim Banner]

....the Zephyr certainly should be able to program any decoder in paged mode (Digitrax says that's their favorite way) on the programming track.

But only if the decoder supports page mode.  Some MRC decoders support only physical mode and I seem to remember some Lenz decoders support or prefer direct register mode.  If you are using a Zephyr, try all four modes.  If none work, try again with the output set for blast mode (but disconnect the main line first.)

[jward]

I tried the 1000 ohm resistor on my programming track with the pr3 and it didn't make any difference.  I used JMRI and also tried the soundloader software on 3 different engines with bachmann decoders.  It would write to them but not read.   I'm going to change them out for digitrax decoders.

Scott

this has certainly been my experience with the dcc onboard locomotives. the 1000 ohm resistor may work sometimes, but it is not reliable. i have not heard of any other workaround. you'd think bachmann would have come up with something but nobody here or anywhere else can tell me anything other than the 1000 ohm resistor.....

i have a friend do all my programming  for me on his nce system. once programmed, the locomotives work fine.....

[Jim Banner]

Jeffery, do you just lay the resistor across the rails of your programming track or do you do something to assure good contact?  I used to have problems with intermittent contact between the resistor leads and the rails.  I ended up wiring  my resistor across the track with a toggle switch in series to cut it in and out as required.  With soldered joints, it works every time.

With the Zephyr, you also have the option of using blast mode programming which broadcasts the programming bytes at full track power to both the programming track and the running tracks.  This means you must either disconnect the running tracks or remove all the locomotives from them, which is a nuisance, but it also means (and this is the good part) that it will program the decoder without having to read back from it.  Seeing as it is the reading back that causes the problem, this mode generally works with all decoders, even ones that do not implement read back.

Jim

[jward]

my setup is a 1k ohm resistor soldered to the rails of the programming track, with test leads connecting it to the zephyr. the test leads might be the problem, i will have to try a more permanent connection.

i was unaware of blast mode. since my layout still has the dc block switches, isolating all other locomotives is not a problem, i can simply turn off track power to any section that has a locomotive in it. i purposely left the dc wiring in place for ease of troubleshooting, and as a backup if anything ever happened to the zephyr.

[kevin2083]

I have only been able to succesfully program decoders on PHYS mode........ but oh well, as long as it works