Thanks very much you guys. I appreciate the answer.
Mars and Gyra lights operated similarly to each other. The Mars light is made by the Mars Signal light company. The Gyro light was made by Pyle National. Depending on the mechanism the light either waved side to side, up and down or the more common figure eight. Designed to draw more attention to the oncoming vehicle/ locomotive. Fire apparatuses also had the lights.
http://en.wikipedia.org/wiki/Mars_Light
There are too many ways in configuring decoder lighting to list. There are more coming out every so often too. The QSI Titan decoder can have 10 lighting functions enabled. There is really no standard except the common wire colors. Most newer decoders can use any one of the function wires for any light possible. You can use the white wire normally the headlight to power a fire box flicker if you want.
Just a small list of lights on a typical modern steam locomotive. Not including a simulated fire.
1 Head light.
2 reverse light.
3 cab interior light.
4. coal space lamp.
5. pilot markers.
6. smoke box class lamps.
7. tender markers.
8. if equipped mars or gyro light.
Diesels have even more lights. Engine room lamps, step well lamps, number boards, ditch lamps and strobes.
Many choices to wire.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
What is done with the green and violet wire will greatly depend on the brand and model of decoder. Decoders for steam locomotives obviously will not have "ditch lights" on the green and purple. I have decoders with two violet wires that are for speakers for the sound......
(Mars light, Gyra etc) that are often associated with those lights, and what kind of scenarios in real life would trigger those light FX
The only time I've used a green output was for marker lamps. Long before the days of ditchlights. Likewise I used purple for the letter boards (In addition to the letter boards on the nose, FT units have lighted loco numbers on the side of the engine).
I am trying to understand the different ways that you will generally find DCC train lights are wired, and how that corresponds to the four colored wires in a 9 pin harness (white,yellow,green,violet).
I've made a sketch here where I identified the 3 most basic ways I know train lights are often wired.
This includes front-only, front+rear, and front+rear+ditchlights. I know many trains have a siren on top, and others have upper headlights and lower headlights. What I'm trying to understand is what the typical light configurations are, and how these are generally wired in relation to the 4 colored wires in a harness. Extra credit for the light animations (Mars light, Gyra etc) that are often associated with those lights, and what kind of scenarios in real life would trigger those light FX. Thank you