I knew this was too good to be true...

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IronBeltKen

Lazy Daydreamer
My new Digitrax system worked fine this morning when I was running it. But when I went to use it later this evening, it didn't respond at all.

My only decoder-equipped loco is an Atlas Gold Dash8-40CW. I tried resetting the decoder's factory defaults, and it always says "Good" when I press the ENTER button to store a CV value. But when I try to read the 4-digit address, it says "Fail". All the lights on the command station indicate what they are supposed to, and I can run analog locos on the test track.

So...did I somehow fry the decoder when I tried resetting it? Is there anything I can do to salvage it?:confused:
 

RexHea

RAIL BENDER
Ken, you can only read back the Address and CV values in the programming (pg)Page Mode. Usually done on a test track. Did you use Page Mode or Ops Mode for your readback?
 
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IronBeltKen

Lazy Daydreamer
I'm not following. It says fail when you try to read the 4 didgit address or when you try to set it?
When I try to read it. [Whenever I've read it before, it showed the correct value - the loco number.]

I can set any other CV and it says "good"; but when I dial-in the 4-digit address and press ENTER, it replies "Ad4on=y".

Ken, you can only read back the Address and CV values in the programming (pg)Page Mode. Usually done on a test track. Did you use Page Mode or Ops Mode for your readback?
Page mode, on the test track.
 
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IronBeltKen

Lazy Daydreamer
This just in...:

On the Atlas forum, somebody suggested I try address 03 since I did the factory-defaults reset, and that worked - now at least I know the decoder's not dead!

All I need to do now, is figure out how to setup for 4-digit addresses again (instead of 2-digit):eek:

Thanx for the replies, guys!
 

SpaceMouse

Fun Lover
On the Atlas forum, somebody suggested I try address 03 since I did the factory-defaults reset, and that worked - now at least I know the decoder's not dead!

All I need to do now, is figure out how to setup for 4-digit addresses again (instead of 2-digit):eek:

Thanx for the replies, guys!
You need a program track. You may be able to do a lot of things programming on your running track, but you can do lot more with the program track.

Put your loco on the program track. Push the program button. It should read AD02. Push the right knob to change it to AD04. Punch in the 4-digit address. Push enter. It will ask a question. Answer yes. (The question may repeat). When it says okay, push exit.
 

IronBeltKen

Lazy Daydreamer
You need a program track. You may be able to do a lot of things programming on your running track, but you can do lot more with the program track.
Ooops...I typed "test track" when I meant to type "programming track". I've had it on the programming track all along.
Put your loco on the program track. Push the program button. It should read AD02. Push the right knob to change it to AD04. Punch in the 4-digit address. Push enter. It will ask a question. Answer yes. (The question may repeat). When it says okay, push exit.
Chip, I'm doing the above steps exactly as you described them, and not seeing any error messages. But it still refuses to accept the 4-digit address - it stays at 03. Whenever I do a readback, it says "ad4==Fail".
 
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grande man

Bonafied Grande Nut
As for frying decoders, we've only had one faulty unit in the last 7 years of DCC, and it was defective from the start. There are ways to fry certain brands, but it doesn't happen often (and usually requires a system booster set up problem, ask cprman;) ).


I'd suggest a factory reset and then attempt to program as usual. Have you changed any other CVs?
 

IronBeltKen

Lazy Daydreamer
UPDATE: QSI decoders don't work well on programming tracks

Guys,

I've gotten some interesting replies to this question on the Yahoo Digitrax message board.

Apparently there's a recurring problem with QSI decoders, where you can program any CV except the 4-digit address sequence on the programming track. Many people who own QSI-equipped locos never learn this, because they never had to do a factory defaults reset and their locos come packaged with the 4-digit address already stored. [That was the case with my Atlas Dash8-40CW.]

The workaround apparently is to set CV17 and CV18 directly, via the online programming mode. I'll try that when I get home...
 

RexHea

RAIL BENDER
Remember to use this calculator for the CV17 and 18 values. You have to convert your numbers. http://ruppweb.dyndns.org/xray/comp/decoder.htm

Don't forget, doing this manually, you have to set CV29, bit#5, high, to accept 4digit addressing. I enter x32 for the CV29 value. Here is another easy chart: just look at the right hand column for four digit and then select the functions you want. Enter that value. http://tonystrains.com/technews/cv29-lookup.htm

Ken, I don't know of the problem that others mentioned, but I do know that some have to buy a programming booster (Tony's) for their programming track. I didn't for any of my (10) QSI programming, but did for the Tsunami.

If all else fails, contact Tony or Ken and I guarantee they will give you good advice.

FYI: If you wire through a toggle switch, you can have the test track and programming track the same (insulate from other track, of course). Very convenient.
 
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SpaceMouse

Fun Lover
I've never had a problem with QSI, so it might just be one decoder or a series of decoders with the problem. I doubt you need a booster with your 5a unit, but I could be wrong.

By the way. I remember that Dash-8 and I'm still jealous of those ditch lights.

Guys,

I've gotten some interesting replies to this question on the Yahoo Digitrax message board.

Apparently there's a recurring problem with QSI decoders, where you can program any CV except the 4-digit address sequence on the programming track. Many people who own QSI-equipped locos never learn this, because they never had to do a factory defaults reset and their locos come packaged with the 4-digit address already stored. [That was the case with my Atlas Dash8-40CW.]

The workaround apparently is to set CV17 and CV18 directly, via the online programming mode. I'll try that when I get home...
 

RexHea

RAIL BENDER
Chip, hopefully he doesn't need a booster, but the 5amp or 8 amp track power doesn't apply to the programming voltage. The programming current is very small (ma) in comparison. The problem stems from the large capacitors used in the QSI (all sound) circuitry. They will try to charge each time you send a program signal. (There isn't any other power on the programming track. This only occurs when you hit the program button.) This will take away from the power needed to program the chip. The booster will first charge the caps and then amplify the signal many times to overcome this problem.

This may help to better explain. http://tonystrains.com/technews/powerpax.htm

KEN:
The manual programming of CV17,18 may overcome the problem. You can program this in the Ops mode and on a regular track. You just have to be careful that you are only programming the one loco. Start out with a reset where your loco is in the default "03" address. Also, be sure to program CV17 before CV18.

As I have said, I didn't have any problems with the QSI, but many have been amazed at that fact. It is (was) apparently very common.

EDIT: One question Ken! Will the loco program a 2 digit address?
 
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grande man

Bonafied Grande Nut
As I have said, I didn't have any problems with the QSI, but many have been amazed at that fact. It is (was) apparently very common.

We've only got one QSI equipped loco but fortunately didn't have any programming issues that required a booster either. I was ready to head to Ray's house if we did. ;)

Ken, There's definitely a learning curve you're dealing with. Things will get easier as time goes by and 6 months from now this stuff will mostly be second nature. If you're like the rest of us, you'll look back and wonder how you could have possibly lived without DCC for so long.
 
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IronBeltKen

Lazy Daydreamer
Hi guys,

Just an update: My loco is back in action as 'itself' again (yee-haw!)

I followed a Yahoo Digitrax group member's plan of directly programming CV17 & CV18 [plus CV29] in "ops" mode. I tested it and it ran like a Swiss watch.

I'm soooo glad I'm doing all this learning activity separate from the layout. I've already caught myself several times pressing what I thought was one button, except I was 'off' by one row - this could well be what hosed my decoder yesterday.:eek: Gotta actually look at each button I intend to push.

Rex, I may very well end up buying one of those Tonys boosters so I can actually use a programming track - that's one of the reasons I bought a DCS100, I heard too many horror stories of other people's decoders being hosed due to careless ops-mode programming on a busy main line. BTW - that's a great online conversion calculator! I didn't need it because I had the original 'cheat sheet' that came with my loco with all the CV17 and CV18 values for each road number.

Eric - I hear ya! Knew it all along actually. I just didn't realize I can 'toggle' my layout between analog and DCC; thought it was a final, all-or-nuthin type of conversion.

Chip - no need to be jealous of the ditchlights, I'm faced with the prospect of having to manually install them on dozens of other locos [if I want them to appear 'correct' for the 1990's]:eek:
 

SpaceMouse

Fun Lover
I doubt you "hosed" your decoder by pushing the wrong button. I have known decoders to reset when the short on a turnout, etc. But never by pushing the wrong button. I caught my son machingunning the knob you push to change directions so that the engine was doing a wierd herky-jerk and the decoder survived.
 




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