Basics of Programming
It is a good idea to set up a standardized system so you don’t forget the Lock Code settings. You might, for example, set all motor decoders to a CV Lock Value of 1, sound decoders to a value of 2 and function decoders to a value of 3. Keeping CV 15 set to 0 will guarantee the decoder stays locked until you are ready to begin programming.
Example: Let’s say you will be installing motor decoder, a sound decoder and a function decoder in one locomotive. Using the previously described system, you would first install the motor decoder and set its Lock Code by programming CV 16 to 1. Since CV 15 is currently set to 0 (the default value), the decoder is immediately locked. Now install the sound decoder and set its Lock Code by programming CV 16 to 2. Since CV 15 is still set to 0, this decoder is also immediately locked. Now install the function decoder and set its Lock Code by programming CV 16 to 3. At this point, all three decoders are installed and locked. Starting with the motor decoder, set CV 15 (the Unlock Code) to 1 to unlock and program the motor decoder. When you are finished set CV 15 to 2 and program the sound decoder. Finally, set CV 15 to 3 and program the function decoder. When you are done, set CV 15 back to 0 to lock all the decoders.
If You Forget the Lock Code As there are only eight possible combinations, you can easily determine a forgotten Lock Code setting using trial and error with the following procedure:
Place the locomotive on the Programming Track and set CV 15 to 0. Then try to read the value in CV 16. If CV 16 does not read back, the decoder is locked. Set CV 15 to 1 and try reading CV 16 once more. Again, if CV 16 does not read back, the decoder is still locked. Program CV 15 to 2 and try reading CV 16 again. Continuing in the manner, you should eventually find the value stored in CV 16 as it can only be programmed between 0 and 7. If you have tried setting CV 15 to all eight values between 0 and 7 and the decoder still does not respond, there may be a problem with the installation, the program track or the decoder itself and further investigation will be required.
If you do not have access to a programming track with read-back capabilities (or are uncertain as to whether it is working properly) you can also use operations mode to discover the Lock Code by alternately programming CV 15 and setting another CV to a value where there is a known response. For example, changing CV 128, the master volume control, will provide auditory feedback as to whether the decoder is unlocked by virtue of a change in sound level. Thus, you would begin by setting CV 15 to 0 and then setting CV 128 to 0. If the volume does not fall to zero, the decoder is locked. Then set CV 15 to 1 and try programming CV 128 again. Repeat this process until you find a value for CV 15 that results in a change in sound volume as you change CV 128.
Troubleshooting Tip Be aware that even if you are not planning to use the CV Lock feature, it can still be accidentally activated by inadvertently programming CV 15 or 16 with a non-default value. If you have a decoder that is otherwise working
Tsunami Steam Sound User’s Guide