This is how the Chief's programming
track is wired. With it, the track power bus gets power directly from
the booster's track power outputs. Instead of turning the rest of
the layout off and on, you use a Double-Pole Double-Throw (DPDT) toggle
switch to switch the programming track between track power and programming.
The beauty of this method is that,
at least with the Chief, the programming track output has limiting
resistors built in. The main purpose for this is to limit the amount
of power that can go to the programming track when programming. This
provides a little extra protection from frying a decoder if you wired
it wrong. The tip here is that when you do a decoder installation,
the first thing you do is program it - before test running it. If
it won't program, chances are you wired it wrong. Had you put it on
the track to test run it, chances are the decoder would have fried.
The secondary benefit of a separate
programming track output is that you can't accidentally reprogram
all the locos on the layout. If you forget to throw the toggle switch,
the decoder on the programming track simply won't program. Even if
you accidentally allow the loco's trucks to span the isolating gaps,
the other decoders on the layout will be trying to draw so much of
the programming power that the limiting resistors won't allow anything
to be programmed - not even the loco on the programming track.
With Service-Mode Programming, any
decoder (regardless of its address) on the programming track will
be programmed when the programming takes place. This means that if
you have two decoders on the programming track and you program the
address for 25, both decoders will assume the address 25. However,
this does not mean that you really can, or should, do this. While
this will work most of the time, the design is that only one decoder
is programmed at a time. We'll cover this more at the end of this
page.
If you want the programming track
to be a part of the layout, where should it be? Many people instantly
think it should be a short out-of-the-way yard track. While this may
seem like the logical thing to do, doing that makes it very tedious
to use. Think about it. To use that track, you have to run the loco
from wherever it is to that programming track. Once configured, you
have to run it out onto the mainline for testing. If it isn't quite
right, you then have to run it back to the back of the yard for re-programming.
Personally, I have my programming
track right on the mainline in front of the main control panel. When
I get a new loco, I place it on the programming track (right in front
of the control panel where I sit) and program it. Once programming
is done, the loco is already sitting on the mainline ready for testing
and re-programming if necessary. A good alternative is a siding
right off of the mainline.
Layouts that do not have a separate
programming track output must be turned off for programming. Many
systems with a separate programming track output also have to turn
the layout off while programming. The Chief, with its separate programming
track output, can continue to run the layout while programming. As
such, you can do programming during an operating session. This allows
you to have multiple programming tracks, so people can do whatever
programming is necessary wherever they are around the layout.
All you have to do to have multiple
programming tracks is run a programming track bus around the layout,
like a track power bus. Wherever you want a programming track, simply
isolate a piece of track and run the toggle switch off the track power
and programming bus to it. Just be sure no one else is using one programming
track while you're using another.
So why not program two decoders at
once? There are two main reasons: ping back and different use of CVs.
When the system sends out the programming
code, it checks to see if there is a decoder present. If not, the
display on Digitrax's throttles shows "No-D". There are
several reasons you may get this message: you may have forgotten to
flip the programming switch, the programming track wiring may have
developed an open, the loco wheels/track may be dirty, the decoder
installation may be faulty, or the decoder may be faulty. Whatever
the reason, the system did not detect a load on the track. So, if
you put two locos on the track and one has a defective "whatever",
the system will detect the good one and do its programming. You will
have no indication or idea that the other one is not programmed.
Next, when programming a decoder,
the decoder will ping back if the programming was accepted and executed.
When the system gets this ping back, it shows "GOOD" on
the display. Again, if you have two locos on the track to program
both decoders at the same time, are they both good? You have no way
of knowing. One could be making good contact, and not the other one
- you won't know that one didn't get programmed. Even if you did know
that one didn't get programmed, you wouldn't know which one.
More important than that is the fact
that not all decoders use the same CVs for the same things. This is
most important for people to understand when they install a DSX sound-only
decoder in a loco with another decoder to run the motor and lights.
Things like special lighting effects, sound controls, and other manufacturer
specialty features are all handled in a set of CVs reserved for the
manufacturer's use. Each manufacturer uses these for their own purposes,
none of which are the same. Programming them together will certainly
mess up one of them. For more information, refer to the DSX
Quandary page.
Service-Mode Programming is something
you will need to learn - at least the basics so you can program the
loco address. You do not need to bother with more sophisticated programming
unless you want to use features that require it. |
