Programming ESU Decoders

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CV Programming for CV’s over 255 with ESU Decoders with a Digitrax Command Station

This process is also valid for other systems which cannot address CVs greater than 255.

Courtesy of ESU.

Some older Digitrax Systems do not allow programming of CVs above 255. In order to make full Programming possible, we have implemented an assistance tool. This helps to write the number of the CVs desired temporarily into two assisting CVs (so-called address registers), since the usual CVs cannot be reached.  Afterwards the value of the CV desired will be programmed into another assisting CV (so-called value register). When the value register is written, the content will be copied to the actual desired position and the assisting CV will be set back. Consequently, 3 CVs have to be programmed to write one CV. These 3 CVs are described in the following chart:


CV Name Description Value Range
96 Address Offset Saves the CV number that should be programmed in the hundreds 0-9
97 Address Saves the CV number that should be programmed in the tens and ones 0-99
99 Value Saves the value of the CV to be actually programmed 0-255

Example: You wish to program CV 317 with value 120.

Proceed as follows:

Program the value of the CV number in hundreds in CV 96.

  • In this example: CV 96 = 3.

Program the value of the CV number in units and tens in CV 97.

  • In our example: CV 97 = 17.

Program the desired value in CV 99.

  • In our example: CV 99 = 120.


As soon as you have programmed CV 99, the value of CV 99 will be transferred into CV 317. Is the programming finished, CVs 96, 97 and 99 will be reset automatically.

This procedure is ONLY needed when programming CV’s above 255 on some older Digitrax DCC Systems and other systems not capable of CV inputs above 255.