I’ve been tearing my hair out trying to program a Digitrax DZ123 decoder to do one simple thing: have the front headlight non-directional, i.e. it stays on whichever way the loco is running.
According to the Digitrax Decoder Manual the front headlight is controlled by CV49, and by fiddling with CV49 I can indeed make the front headlight flash, or rotate, or do a bunch of other stuff, but I cannot make it stay on when the loco goes backwards!
wakaiti,
What if you connected the yellow (rear headlight) wire and white (front headlight) wire from your decoder together? Blue remains common for both. When you change directions, the light will stay on, no matter what. The one thing that may happen is that the light will blink slightly changing from front to rear headlight.
Tom
On page 59 of the decoder manual it says to set CV61 to 01 .
==========================================
6.14.1 Non-Directional Headlight Operation
Most Digitrax decoders support the independent control of the head light and
tail light. In decoders with this capability, if you don’t want automatic reversing
headlight operation (the decoder’s factory default setting), you can set up the
white output for the headlight to operate on F0 (function 0) and the yellow output
for the rear light to operate independently on F4 (function 4). This lets the
engineer have complete manual control over when these lights are on.
Program CV61 to a value of 01 and the decoder will “map” the normal reverse
light function output (yellow) to be controlled by the F4 function key. In addition
the normal forward light function output (white) will become a non-directional
light output that is controlled by the F0 (light function) button on the
handheld. The FX operation of the white & yellow outputs are still controlled
by CV49 & 50. The FX effects can be made directional if desired by following
the FX programming instructions in this manual. CV50 will still control the FX
effect you are using on the yellow
It’s page 57 of the version I have, but yeah. [:D]
–Randy
Oh, you mean read the rest of the manual! [#oops]
Thanks for pointing me to that. Unfortunately it doesn’t work. There’s a note saying it doesn’t work with DN121 decoders, so maybe that includes the DZ123 series as well. I guess the idea of connecting both front and rear cables to the light is the way to go.
The DZ 123 and the old DZ121 had just 2 functions (Headlight Forward - Headlight Reverse).
That is the designation of the two in the part number 1 (2) 3 - two functions.
The DZ143 has 4 functions and will allow a number of lighting effects.
Unfortunately the manuals for both the DZ 123 and DZ143 are combined and this gives the impression that the DZ123 will do special effects which it won’t
BOB H – Clarion, PA
Won’t that screw something up in the decoder? I didn’t think you were supposed to connect different leads together.
Dan,
That would be true with the track and motor wires, but with the light functions it’s an either/or. So there shouldn’t be any problem with connecting the yellow and white wires together.
Tom
Not necessarily the rest of the manual, but at least the rest of the page. [:D]
In the online version at least, there’s another note in bold under the DN121 note that says for FX3 decoders (as in DZ123), you also have to re-map the functions using CV33 and CV34.
Just just now tried this in an Atlas GP7 with a DZ123PS and it worked like a champ. All I did was change CV61 to 1, and add 1 to CV33.
I didn’t bother with the rear light as I just wanted to prove to myself that it worked before setting the loco back the way it was. But all you’d have do do is change CV34 to remap that one as well.
HTH,
Steve
It’s ok to connect more than one function lead to the same bulb, because the function leads themselves (white, yellow, etc) are actually the ground side of the circuit. The blue common wire is the positive supply. It’s sort of like putting a second drain in your sink. Open one, the other, or both and the water flows. Same with the function leads.
–Randy
Thanks Steve. I changed CV34 to 1 and it works! F0 controls the front headlight, and it stays on in forwards or reverse.
NOW…!!! Is there any way of adjusting things further so that for example the light flashes in reverse? (Non-prototypical behaviour I know.) I’ve tried programming various values into CV49: the effects work but they are non-directional - maybe I can’t have both at once?
Glad you got it working. Don’t know about the flashing you’re trying to get as I’ve never tried that combination before. I’d just suggest that you go over that section of the manual in some detail and try it. You can always reset the decoder and start again if it doesn’t work out.
Steve
To get back to a directional control you have to change CV61 back to 0 (actually subtract 1 from the current value since it’s also used to control transponding, so if you have trnasponding turned on the values would not be 0 for directional and 1 for non-directional).
To have a steady light in forward and blinking in reverse, you will have to hook two functions up to the one bulb. Program F0F to forward steady light, and program F0R to blinking in reverse (0x13, or 19 decimal). When going forward, only F0F will be on, giving a steady light. When you reverse, F0F will turn off but F0R will turn on in blinking mode, making your headlight blink.
–Randy