Brew Man Posted April 12, 2021 Share Posted April 12, 2021 I have a (probably) quite old Jinty that was factory fitted with DCC. I can change the Address but it doesn't seem to respond to other CV changes, such as CV 8/8. I've tried this with both my controllers, (Elite and Select) but nothing changes. Other locos seem OK.Anyone know why this is so? Maybe some older decoders don't support writing to CVs. Link to comment Share on other sites More sharing options...
Rog RJ Posted April 12, 2021 Share Posted April 12, 2021 What make of decoder is it? Some decoders don't use CV 8/8 for resetting.If its an old Hornby R8215 decoder, these will only accept a 2 digit address and don't allow you to read values from any CVs but afaik they should reset with CV8 set to 8. I have read that you sometimes need to reset a decoder a number of times before the reset will "stick". Link to comment Share on other sites More sharing options...
Brew Man Posted April 12, 2021 Author Share Posted April 12, 2021 To be honest I've no idea which decoder is in it. It's a beautiful example that bought on eBay when I was first getting going. As I said, changing its address is fine and works, but writing to any of the CVs has no apparent effect. The reason I wanted to to do this was because the acceleration/deceleration were quite long so I thought I'd speed them up a bit, but writing to CVs 3 and 4 have no effect. It's otherwise a great loco. Link to comment Share on other sites More sharing options...
96RAF Posted April 12, 2021 Share Posted April 12, 2021 Try writing changes in Reg mode (Elite, not Select), noting there are only eight registers you can access.Likely the decoder if a factory fit would be R8215 which tend towards unreliable on a good day and are best replaced. Link to comment Share on other sites More sharing options...
Brew Man Posted April 13, 2021 Author Share Posted April 13, 2021 Ah, that's interesting. So you think it might be more responsive if I try writing to it in Reg mode? Taking your advice, I might replace it with an R8249 at some point. I tried programming with the Elite on an 0-4-0 with an R7274, 4 pin decoder at the same time and it was absolutely fine. Link to comment Share on other sites More sharing options...
Brew Man Posted April 13, 2021 Author Share Posted April 13, 2021 Just as an aside from this, what 8 pin decoder do people most use? I have 3 locos with 8249s in them and I've had no negative experiences with them so far. Link to comment Share on other sites More sharing options...
Fishmanoz Posted April 14, 2021 Share Posted April 14, 2021 For info, the 8249 and the 7274 are the same decoder electronics, just that the latter has no connections for the function outputs. Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now