Function Mapping

[michael.hamilton]

I have an R2900XS sound loco and I would like to adjust CVs so that the airhorn signal (F13) operates when I press function 4 so that I can use it on a layout controlled by a Select.

The loco has a LokSound V3.5 decoder.

I have been reading up on function mapping, but so far I'm a bit lost. 

[Fishmanoz]

I'm no expert but can I suggest the answer must be in the manual for the 3.5, which you can download from the Loksound site if you don't already have it. Somewhere in there it must show the CVs that dermine which sounds relate to which functions and so tell you which ones you need to change. It may be hard to find as the manuals are long because the decodes are very capable and it takes many pages to cover their full functionality. 

[michael.hamilton]

I've found the relevant section in the manual, but I admit defeat in understanding exactly which CVs need to be changed (and pehaps calculated) to achieve the outcome I would like.

Suffice to say I have had to reset the decoder using CV8 several times today.

Perhaps someone can solve it for me.

[Graskie]

I have a feeling you can't do what you want to, michael. I've never needed to change functions and wouldn't really have a clue about how to do it. Don't forget that some of them are universally accepted standard settings, eg F1 always seems to be sound on/off. I assume you've looked up the Loksound site, and perhaps you could ask them whether this can in fact be done. I appreciate your function limitations on the Select and perhaps you would really need to upgrade to an Elite, which I use.

[Augustus Caesar]

@Michael

From what I have read and can understand it is possible to change functions on the Loksound decoder. I have copied the text from the LS 4 manual but assume it will stand up for inspection for the LS 3.5 decoder too.

Whilst I have no experience of these decoders I do understand simple electronics and programming. You may have spotted this text yourself but if not it is within the manual itself on the LS site... page 50.

12.1. Physical function outputs
LokSound decoders have up to 12 physical function outputs. „Headlights“ and „Rearlights“ are used for lighting, the remaining ones are freely available. Other functions include „Shunting Mode“, „Acceleration / Deceleration On/Off“ as well as virtual functions like „Sound On/Off“.
The function buttons („F buttons“) of your command station or throttle activate the function outputs.
Generally, F0 is the lighting button, while we count the remaining buttons from F1 upwards.
12.2. Allocation of Function Buttons (Function Mapping)
LokSound V4.0 LokSound micro V4.0 LokSound XL V4.0 LokSound V4.0 M4
You can allocate the functions freely to any function button. ESU uses the so-called and once more extended „Mapping“ for the LokSound V4.0 decoder. It has the advantage that you can link each output to any button. Furthermore, the allocation can vary between forward and reverse as well. It is also possible to switch several functions simultaneously. Unfortunately this kind of flexibility requires a large amount of CVs. The solution of this problem is called “Index CV access”.

Whilst, as I say I have no experience of said decoders yet I do hope this may help you if you read past the text in the manual I give you here.

[michael.hamilton]

Both CV 309 and 318 read 0.

[michael.hamilton]

Thanks for your reply.

I've read the corresponding section in the LS V3.5 manual but I'm afraid I don't understand exactly what I need to do.

[michael.hamilton]

Thanks for your reply.

The LS V4 manual refers to CV 31 and 32 as index registers. There is no mention of them in the V3.5 manual.

I have studied the enormous table and I'm afraid I don't understand it.

[michael.hamilton]

Thanks for your reply.

The LS V4 manual refers to CV 31 and 32 as index registers. There is no mention of them in the V3.5 manual.

I have studied the enormous table and I'm afraid I don't understand it.

[michael.hamilton]

Cv 167 was 003 and Cv 227 was 008.

Swapped the values over but it doesn't seem to make any difference.

[HFM]

If your other controller is compatible will decoder pro not do this for you, its free

paste the link http://jmri.org/manual/3-0_DecoderPro/Comp_FMap.shtml and have a read.good luck

[michael.hamilton]

Hi Magfan.

Thank you so much. At first I thought that swapping the values of CV 167 and 227 had made no difference, because I still heard a sound (not the airhorn signal I wanted) when I pressed F4.

But when I started trying other values in CV 167 I noticed that this changed the sound for F4.

With a bit of trial and error I have found that a value of 11 is what's needed to activate the air horn signal.

Thanks again for taking the time to help me out.

[Graskie]

Very interesting conclusion, guys. Could come in handy at some time in the future. Sorry, I guessed wrong. It can be done then. Great!

[Fishmanoz]

Glad you got my reply Michael, because if you look now, I think it's gone missing. 

Anyway, now you have some idea what you are doing, take another look at that table and see if it makes any sense?

[Augustus Caesar]

Well done guys for helping Michael out. I knew there was a way of programming these things but I've not got one and have no experience of them. But a mate has and I was certain he did this somewhere along the way.

I couldn't find the manual for LS 3.5 but it may be handy if I were to use it in future so does anyone have a link? I've had little time to search this out to be honest and if someone can help me out this once I will send them a virtual drink of their choice for them to enjoy at leisure... :-)

[Augustus Caesar]

Many thanks for that Michael. I'll have a read of it over several cups of tea (it's gonna take a while!!) and try and digest what's going on. I have the v4 manual and will compare eventually too.

Thanks again. :-)