Sir TophamHatt Posted February 11, 2018 Share Posted February 11, 2018 I'm a bit confused on how to program CV29. I have a few hard wired locos that I need to change the Polarity for. Most, if not all have a Lenz Silver Plus v2 in them. The manual suggests there are a few individual settings within CV29 and I'm aware that messing up this particular CV means potentially starting again. The Lenz manual says CV29 but then has 'Bit'with a series of 1-6 for individual settings. It's currently set to default 6 but I don't understand what to change this to if I want to change a coupe of the individual settings, such as Polarity and operational mode. Any advice? Cheers Link to post Share on other sites More sharing options...
RMweb Gold Oldddudders Posted February 11, 2018 RMweb Gold Share Posted February 11, 2018 http://www.2mm.org.uk/articles/cv29%20calculator.htm Link to post Share on other sites More sharing options...
smokebox Posted February 11, 2018 Share Posted February 11, 2018 (edited) This may help https://ncedcc.zendesk.com/hc/en-us/articles/200537669-CV29-Explained Edit for typo Edited February 11, 2018 by smokebox Link to post Share on other sites More sharing options...
RMweb Premium melmerby Posted February 11, 2018 RMweb Premium Share Posted February 11, 2018 (edited) I'm a bit confused on how to program CV29. I have a few hard wired locos that I need to change the Polarity for. Most, if not all have a Lenz Silver Plus v2 in them. The manual suggests there are a few individual settings within CV29 and I'm aware that messing up this particular CV means potentially starting again. The Lenz manual says CV29 but then has 'Bit'with a series of 1-6 for individual settings. It's currently set to default 6 but I don't understand what to change this to if I want to change a coupe of the individual settings, such as Polarity and operational mode. Any advice? Cheers Why not invest in a Sprog? Then you can do everything using convenient, understandable menus using JMRI DecoderPro Keith EDIT If you hard wired it why not just swap the wires around? Edited February 11, 2018 by melmerby Link to post Share on other sites More sharing options...
Lady_Ava_Hay Posted February 11, 2018 Share Posted February 11, 2018 I'm a bit confused on how to program CV29. I have a few hard wired locos that I need to change the Polarity for. Most, if not all have a Lenz Silver Plus v2 in them. The manual suggests there are a few individual settings within CV29 and I'm aware that messing up this particular CV means potentially starting again. The Lenz manual says CV29 but then has 'Bit'with a series of 1-6 for individual settings. It's currently set to default 6 but I don't understand what to change this to if I want to change a coupe of the individual settings, such as Polarity and operational mode. Any advice? Cheers Most decoders come with an instruction sheet which details which bit does what and its default value. You then add all the bit values you have assessed as needed and enter that value in CV29. This CV and it's bit values are the same in every decoder that conforms to the Lenz protocol as detailed by NMRA. A simple change of the value of CV29 for direction of travel to match the controller is simple enough but this CV also controls use of a speed table, also pre programmed in the decoder, and a fair amount of other variables. This is where it then becomes advisable to have a device that will give a GUI ( graphical user interface ) that makes changing the value of CV29 a much easier job. Since every decoder you have will respond in the same way to this programming ability, it is a good investment. I started with DecoderPro and a Sprog mark 1 (!) and only abandoned that set up when I started using Digitrax equipment and getting involved in DCC sound. At the time we are talking ( 10 years ago at least ) DecoderPro was none too good at the myriad of CV's that sound decoders represented as each and every DecoderPro file required some volunteer to actually sit down and write the code for it and then test and load to the DecoderPro website for others to use. Things are different now and I imagine that using up to date software and hardware will make your life a lot easier mainly because you can see on a computer screen what changes you are making before you make them whereas a controller writing CV's to an installed decoder is a one at a time exercise and, unless notes are taken, easily forgotten as to values and changes made. One can rely on a decoder reset but that will return the decoder to its default values and ALL changes will be lost. Link to post Share on other sites More sharing options...
Sir TophamHatt Posted February 12, 2018 Author Share Posted February 12, 2018 Why not invest in a Sprog? Then you can do everything using convenient, understandable menus using JMRI DecoderPro Keith EDIT If you hard wired it why not just swap the wires around? Yeah, I thought about [investing in a SPROG] but I'm equally happy to save the £40 odd at the moment. There was one on ebay but went for the price of a new one so no point really. However, now the chips are in and the locos back together, I'd rather just change the setting on the chip than faff about soldering again Read through the website, that's a pretty good explanation - adding the "bits" together to get the value seems sensible. Just a shame a fair amount of important bits are all lumped together in the one option! Link to post Share on other sites More sharing options...
Pete the Elaner Posted February 12, 2018 Share Posted February 12, 2018 Maybe you don't need a Sprog? What system do you have. Some of them have either a USB or Serial port included, so you can hook up a PC straight to that in order to run JMRI. Link to post Share on other sites More sharing options...
GoingUnderground Posted February 12, 2018 Share Posted February 12, 2018 (edited) Because of the way that the values work in CVs, it is very easy to change the direction of travel when the controller is set for forwards running, provided your DCC controller can read CVs, and the decoder will also support reading CVs. Read CV29. If it is an odd number, SUBTRACT 1, and write that new value to CV29. For example, if the value of CV29 is 7, then 7 - 1 = 6, and that is the value you write to CV 29 to reverse the direction of travel. However, if CV29 is an even number, then ADD 1 to the value of CV29 and write that new value to CV29. For example if CV29 is 8, then 8 + 1 = 9 and that is the value you write to CV29 to reverse the direction of travel. As CV29 in your loco is currently set to 6, I think you said, then simply write the value 7 to CV29. Do not try writing the value 1 or zero to CV29 as in most circumstances that will override the settings for the other decoder attributes governed by CV29. Edited February 12, 2018 by GoingUnderground Link to post Share on other sites More sharing options...
Sir TophamHatt Posted February 12, 2018 Author Share Posted February 12, 2018 (edited) Prodigy Advance 2. I think it has a port but it's "factory use only". Asked this elsewhere but seems appropriate here also: Is there an advantage to setting DC operation = OFF if I am never going to run the train on DC? I'm digital all the way and only use a couple of metres of DC track to test some older trains (40+ years!) I have in rediness to convert to DCC. Edited February 12, 2018 by anotheruser Link to post Share on other sites More sharing options...
johnb Posted February 12, 2018 Share Posted February 12, 2018 I do set DC 'OFF' as I have found that it improves the stability of some chips. I did have some that tended to 'run-away' or operate erratically, so now I automatically set DC as 'OFF' on any chipped locos. If I do want to run a loco on DC it's easy enough to change the settings. I use an NCE Powercab which has that as part of the menu system, so no changing CVs manually as the Powercab does that for you. John Link to post Share on other sites More sharing options...
pdj49 Posted February 13, 2018 Share Posted February 13, 2018 To reverse the polarity just add 1 to cv29. If yours is reading 6 then change it to 7. Taunton Controls offer a helpline for such problems. The phone 01823 327155 is open 9am to 9pm, 6 days a week (closed Wednesdays). Link to post Share on other sites More sharing options...
smokebox Posted February 13, 2018 Share Posted February 13, 2018 That's too simplistic. If CV 29 is an odd number you have to deduct one from that value. Link to post Share on other sites More sharing options...
JJGraphics Posted February 13, 2018 Share Posted February 13, 2018 You don't need any fancy kit. The Gaugemaster Prodigy Advance2 will do the job! See post #2 above . . . the information in that link is solid gold and all you need. IMHO it is a good idea to turn off DC operation if you never intend to use it as DC operation being active is sometimes attributed as the cause for uncontrolled runaways. John Link to post Share on other sites More sharing options...
Crosland Posted February 13, 2018 Share Posted February 13, 2018 To reverse the polarity just add 1 to cv29. If yours is reading 6 then change it to 7. And if it reads 7 you end with 8 which has cleared two and set one completely different bit. Simply adding/subtracting, without more detail and caveats, is the worst possible advice! Link to post Share on other sites More sharing options...
RAF96 Posted February 13, 2018 Share Posted February 13, 2018 Having DC enabled has advantages for as simple a task as wheel cleaning with a 9 volt battery across the wheels to activate them for scrubbing clean. Rob Link to post Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now