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DCC Programming: episode 9 - Demystifying CV 29
I really appreciate Dana’s “plain English” explanations of DCC. Please keep 'em coming!
Another wonderfully insightful & informative film Dana. Keep up the sterling work as this is the way forward for the next generation of model railroaders!
Excellent job, Dana! Thank you for the split-screen views - makes understanding what you do/are doing MUCH easier.
While I DO agree with everything you said about “bit 0”, I have to disagree with one of the reasons. Yes, it is MUCH easier to change the direction of the locomotive by changing CV29 rather than de-soldering and re-soldering the motor wires. However, by changing the wires you don’t have to remember that engine 4551 and 2300 and 8422 and 4884 have been changed using CV29 and they run “backwards” correctly. Oh, did I remember engine 2300?
Why do I always forget to rate the video?
Hi Dana,
really love the work you are doing in this space. Your instructions are so easy to follow.
Just one minor technicality - the toggle switches used to graphically represent the bits in a byte should be drawn with bit 0 on the right side and bit 7 on the left. e.g 10000000 in binary = 128 digital, not 1 digital.
But I get that you are trying to use a visual representation of the bits.
Excellent video. CV29 has been mystery to me since my system has so far automatically updated it. I was apprehensive about changing the values. You have taken the mystery out of this CV.
Dana, great series of DCC videos! More videos like this series would be fantastic! Keep up the good work!
Seems your still into showing the bits backwards from left to right - You should start with bit one on the right not on the let. Having to now binary programing as part of my old job it just boggles the mind when some one shows things wrong or backswords and the way you have it is backwards and shows another number than you think it should. People talking about DCC programing as hard, well if you show something other than the norm it can be highly confusing.
Excellent explanation of CV29. I have read several explanations/clarifications of CV29 and this was the first time I really understood it. Thanks Dana.
Hi Eric and Michael,
We struggled a bit with how best to show this in the simplest way possible. Yes I know that in computer programming the bits would start on the right. Since most people read left to right, and to avoid having to complicate the issue by explaining why we were showing it from right to left, we decided to show the switches as we did. For simplicities sake, I chose to avoid any discussions of binary math, and focus on how to get the locomotives to do what you want.
As always thanks for your comments,
Dana Kawala
Senior editor
I’ve tried using CV29 to reverse a mis-wired loco and have found that the lighting doesn’t reverse. Rather than rewiring or reprogramming the lights, I found it much easier just to swap the motor wires.
Thanks, Dana for this series. It’s helped me a lot!
Thanks Dana. This whole series on DCC has been quite helpful! I’m finally getting the idea of “why” some of these things work the way that they do 
Your explanations are easier for me to understand on the video format versus the magazine articles. Looking forward to future episodes.
Thank you for this video. It helped dispel some of my fears in changing CV numbers.
Thank you, Dana; excellent “nuts and bolts” clinic on CV29!
Thanks Dana, Very clear explanation. The “fear” factor is gone in
programming CV29
Thanks Dana. This really helps me understand CV29. Looking forward to more great DCC helpful information.
Good video. The only problem I had is, since I’m a programmer, your bit (switch) example in the beginning is backwards. Left to Right the bits go 128 down to 1; 128, 64, 32…
Thanks Dana, a very good and understandable explanation for us to learn from, as the others have said very helpful. I am enjoying this series a lot
Great job, Dana! Very good series… you make dcc easy to understand… much appreciated! Thanks!