For a number of years I have been thinking through the problem of some sort of standard for function assignments on sound decoders. As we know each decoder manufacturer has decided to use their own 'standard' to suit their particular decoders. I have found this somewhat annoying so hence my 'thinking'.
I have a number of brands of sound decoders and these have varying capabilities. I can't afford to change out the older decoders for the latest types so I have to work with what I have.
I have first generation Soundtraxx Tsunami, latest Soundtraxx Tsunami 2, first generation QSI, QSI Titan and ESU Loksound 4 in steam only.
The early Tsunami has the functions in groups that is not every sound or lighting can be applied to any function you may want. This is somewhat restrictive compared with the later Tsunami 2 which can have any sound or lighting set up for any function number.
The QSI and ESU sound decoders also allow a lot of flexibility in aligning sounds and lighting with function numbers.
Working within the constraints imposed by the first generation Tsunamis of which I have quite a few I have now come to what I think is a reasonable set of function assignments or at least ones that suit me and the way I want to operate.
I am not one who wants to 'play a musical instrument' with a lot of button pressing and I am quite happy to allow the decoder to sound those random sounds such as injectors, blowers, shoveling, etc. Manual notching for diesels is also something I don't like as you can easily drive a train at notch one up and down grades with a full train load, not very prototypical.
I would have to say that I really like the Tsunami 2 with auto notching as it reads the BEMF and responds to the load on the loco. If you start a light loco it and use the throttle to notch up to say notch two or three it will do so but then once moving it will drop back and quieten right down. Similarly if it has a train load behind it it will notch up louder and then drop back as it gets the load rolling, very nice.
I also have a steam Tsunami 2 in a NSWGR C35 Bergs brass model and it also responds in a similar manner, chuffing loudly to get the train moving and then dropping back and chuffing lightly or even drifting once the train is rolling.
I believe that the TCS WOW sound decoders also work this way but I don't have one, this is the only reason it isn't included in the tables of function assignments.
I also want to work towards having working marker lights which will be a long process of course as some of the earlier models didn't have them and some decoders do not have enough lighting outputs either.
I have drawn up a diesel and a steam table for my new 'standard' and I have begun to re-program my loco fleet.
I have an NCE DCC system with the standard larger cabs. These cabs have 12 available function buttons but F10, F11 and F12 require the use of a Shift key to access. Functions 0 - 9 are all single press (Function 0 is the headlight). Also of the basic eight functions only six show on the LCD display.
I realise that not everyone will like or agree with my choices but they are of course just my preferences.
Here is a table showing the function assignments for a diesel.
And here is the table for steam.
Please be aware that I model late 1965 and as such the diesel function assignments do not include ditch lights, etc. of modern locomotives.
Most sound decoders only have 4 outputs, some do have 6 and there is one that has 10 and these have been listed on the PDF tables.
For those who are interested there is also a decoder that has 12 outputs and it is one of the Zimo sound decoders.