Knowledge base: Function Decoder

We test all decoders automatically, with a test bench and a dedicated software made by us. This software was improved over the years, and it is used to validate each decoders hardware before it gets the latest firmware and is shipped. All the decoders has to pass this test, and as a result they are validated. Later, before delivery, if it is the case, the decoders are updated with the latest released firmware. At that time, the basic functionality is tested again. Which means, only tested and working decoders leave our factory. If your decoder is not working anymore, some of the information below might help you solve the problem.


1) The long addresses of the OLD(!) function decoder, called FD Basic,  are limited to the range 1-255. This is NOT a limitation with the 2022 function decoder range.


2) Getting the lights to work with the F keys

The problem is that many users expect the decoders to work straight from plugging in. But the outputs on every model can be assigned differently and every model train manufacturer can set their own defaults. That makes it a bit of guesswork sometimes.


When you don't know to which cables the light is connected,  just try to enter value 1, 2, 4, 8, 16 and 32 to CV 35 (one value at the time, then try each value) and see what I turn on when pressing the F1 key.


These are the CV’s to change the output assigned to the F0 light key:

CV33 = F0 forward

CV34 = F0 reverse


Note: This only works if the lights are connected to the white (Output 0 Forward) and yellow (Output 0 reverse) connections.


Value 1 would normally mean that the front light is on, value 2 would be the rear light. So if you would leave CV29 on 14, you would have to set CV 33 to 2, CV 34 to 1. That is, if the lights are connected to the white and yellow cable output. Sometimes the manufacturer connect the four lights (front white, front red, rear white, rear red) to 4 different connections. So besides F0 forwards and F0 reverse, Output 1 and Output 2 are also connected to the lights. Which means you would have to add the bit value to CV 33 and 34. 


3) The direction of the white and red lights is reversed.

You can revert the direction in CV 29, if the white light is on when running backward. Set CV 29 to 15 (the default is 14). This only works if the lights are connected to the white (Output 0 Forward) and yellow (Output 0 reverse) connections.

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