Light Function Mapping in (old) TCS decoders

[melmerby]

Hi all

I am playing around with some old TCS decoders to use for their function outputs.

I have 2 x M3 decoders and according to the TCS blurb and Decoder Pro, I should be able to map the wires (white, yellow & green) to any function key.

However, try as I may I cannot get the green wire to function on anything other than key F2 on either decoder.

 

e.g. I change the mapping to operate on key F5 and check that it has been changed but it still only works on key F2

The mapping is in CV33 -35., Default values are 1, 2, 4. I change CV35 to a value of 64 and it should now operate on F5.It doesn't, it still on F2

The white & yellow can be changed however.

 

I have cleared the other values in the function mapping with decoder pro and just left the three wires mapped.

 

Any suggestions what I might be doing wrong?

 

 

[jpendle]

CV36 controls function output 2, CV35 controls F1, CV’s 33 & 34 control F0f and F0r.

 

Regards,

 

John P

[BromsMods]

Have you tried resetting the decoder back to defaults before programming CV35?

 

Have you tried setting the output to F4 (CV35=32) or F6 (CV35=126)?  Did that work?

 

Out of interest, if you set CV37 to a value of 4 can you then control the green output on F7?

[melmerby]

1 hour ago, BromsMods said:

Have you tried resetting the decoder back to defaults before programming CV35?

 

Have you tried setting the output to F4 (CV35=32) or F6 (CV35=126)?  Did that work?

 

Out of interest, if you set CV37 to a value of 4 can you then control the green output on F7?

Yes

 

Yes & No It didn't

 

Haven't tried mapping to F7

3 hours ago, jpendle said:

CV36 controls function output 2, CV35 controls F1, CV’s 33 & 34 control F0f and F0r.

 

Regards,

 

John P

Not exactly AFAIK

CV33 controls the white wire, CV34 controls the yellow wire and CV 35 controls the green wire.

They can (should) map to any function key, unless I'm mistaken.

 

[jamesed]

1 hour ago, melmerby said:

Not exactly AFAIK

CV33 controls the white wire, CV34 controls the yellow wire and CV 35 controls the green wire.

They can (should) map to any function key, unless I'm mistaken.

 

 

I think that's the point John is making.  With a default value of 4 cv35 is mapped to F1.  However, you have already stated : 

However, try as I may I cannot get the green wire to function on anything other than key F2 on either decoder.

so that means logically you must have a value of 8 on cv35, not 4.  If your cv value is definitely 4 then that implies that the green and purple wires have been reversed somehow. 

 

If F2 is switching it correctly then try mapping cv36 to F5 (cv36 = value 64) and see if that works.

 

 

[melmerby]

22 minutes ago, jamesed said:

 

I think that's the point John is making.  With a default value of 4 cv35 is mapped to F1.  However, you have already stated : 

 

 

so that means logically you must have a value of 8 on cv35, not 4.  If your cv value is definitely 4 then that implies that the green and purple wires have been reversed somehow. 

 

If F2 is switching it correctly then try mapping cv36 to F5 (cv36 = value 64) and see if that works.

 

 

There isn't a purple wire, it's a 3 function decoder with white, yellow & green wires all of which should be able to be mapped to any sensible function key number.

 

I can map the yellow & white wires to any function number, however changing the value of CV 35 (green wire) makes no difference at all, it's always operated by F2 key

(I have two M3 decoders, they both operate the same)

 

These are the current settings

Function Mapping Table:

 

CV settings:

 

 

Edited August 10, 2022 by melmerby

[RedgateModels]

CV35 is zero in the above screen grab?

[melmerby]

11 minutes ago, RedgateModels said:

CV35 is zero in the above screen grab?

Because on the suggestion of John@Bromsmods I had changed to the alternative of CV 37=4 for the green wire, which changes CV35 to zero. (there was no difference)

 

e.g.

Edited August 10, 2022 by melmerby

[jamesed]

So what value have you got for cv36?

 

This must be the key because if F2 is operating it then that's the value you want to know. 

[Nigelcliffe]

I'd suggest faffing around with other CVs and see if anything happens to change stuff.  

 

I remember, quite a few years ago, doing some things with TCS decoders and hitting a problem.  I emailed TCS support to try to find out why I couldn't get it to work, the reply was (paraphrasing) " oh, that doesn't work like that anymore, but we didn't want to confuse people by changing the manuals ".   

 

 

- Nigel

[jamesed]

Sorry, I've just realised that we may be all heading up the wrong path here.  If the decoder is following standard NMRA protocol then your 'green wire' (which is accessory function FA1) can only be operated by F0f F0r F1 or F2.  The table below is taken from a Zimo manual but it shows the offset that exists in the NMRA standard which is quite limiting.  ZImo does have a work around for this which is specific to their decoders (cv61=97 which removes the offset). Unless TMC has something similar then you may have to stick with F1 or F2 I'm afraid. 

 

 

 

[BromsMods]

Exactly how old is the decoder, Keith?  You can find out using the following:

 

Version Number
Version Number CV 7
When major bug fixes or upgrades are done to the software in the decoder the version number is updated. For troubleshooting tech support representatives at TCS may ask for the version number which can be read out of CV 7.
Date Code
Month Programmed
CV 250
Day Programmed
CV 251
Year Programmed
CV 252
Each decoder that is programmed has the date it is programmed stored in CV’s 250, 251, and 252. If you contact TCS with a software related glitch or concern reading out the date code can help us identify when your decoder was made and more succinctly diagnose the problem.

[melmerby]

2 hours ago, BromsMods said:

Exactly how old is the decoder, Keith?  You can find out using the following:

 

Version Number
Version Number CV 7
When major bug fixes or upgrades are done to the software in the decoder the version number is updated. For troubleshooting tech support representatives at TCS may ask for the version number which can be read out of CV 7.
Date Code
Month Programmed
CV 250
Day Programmed
CV 251
Year Programmed
CV 252
Each decoder that is programmed has the date it is programmed stored in CV’s 250, 251, and 252. If you contact TCS with a software related glitch or concern reading out the date code can help us identify when your decoder was made and more succinctly diagnose the problem.

Hi John, it's pretty old (any any original literature I had was lost when my railway room flooded 4 years ago).

CV 7 = 45

CV250, 251 & 252 are all empty (=0)

 

Same readings via Decoder Pro & also directly with a command station.

 

EDIT

I have a M1 decoder which is version 47 (later than the M3) and has a date code of d=25 m=10 y=8, so the M3 must be earlier than that

EDIT 2

All the other M1s are either version 47 or Version 49, late 2008 to mid 2009

Edited August 10, 2022 by melmerby

[BromsMods]

I don't have instructions for an M3 decoder that old but I do have instructions for an M4 for the same period.  It looks to me that these older decoders don't have the ability to remap functions or provide the date of production, so I'm afraid that it appears your M3 won't do what you want of it.

[melmerby]

1 hour ago, BromsMods said:

I don't have instructions for an M3 decoder that old but I do have instructions for an M4 for the same period.  It looks to me that these older decoders don't have the ability to remap functions or provide the date of production, so I'm afraid that it appears your M3 won't do what you want of it.

Thanks for the info John.

 

At least that confirms what I am finding. (You can actually map the white & yellow wires as I have done that but not the green which is permanently operated by F2

I'll just have to use it as it is.

I was concerned because some command stations do not latch F2 as it was originally intended just for a horn or bell, but it seems mine doesn't have that problem.

I need all three outputs to be latching on/offs