Decoder Settings (Programming); Changeable Decoder Settings; Configuration Variables (Cv); Standardization Regarding Nmra - Esu 51801 Instruction Manual

Decoder settings (programming)

7. Decoder settings (programming)
Chapter 7 is about changing the settings of the SwitchPilot de-
coder. In case you are not familiar with the CVs please take some
time to read through the sometimes very complex explanations.
After an introduction into the world of parameters in Chapter 7.1,
Chapter 7.2 explains how to change the parameters with different
DCC control units.
Chapters 8 through 11 explain which parameters influence the
behavior of the SwitchPilot decoder

7.1. Changeable decoder settings

Certain capabilities of the SwitchPilot decoder like the amount
of function outputs or the maximum current load are physically
limited through hardware and are not changeable. However, there
are still plenty of possibilities to change the behavior of the Switch-
Pilot decoder through software changes.
For each individual parameter there are one or more storage lo-
cations within the decoder in which numbers or letters can be
stored. You can think of these storage locations as index cards
which are kept in a large file cabinet. In order to find the indivi-
dual index cards each one has a number or description with the
property of the card, e.g. „Loco Address" or „Maximum Speed".
Now imagine that those cards can be written on with a pencil;
changes are always possible through erasing and writing. Not all
„cards" can be written on. Certain pieces of information like the
manufacturer identification for ESU are hardcoded.
The content of these storage locations can be chosen by you and is
being read and considered by the decoder. You can fill the storage
locations with any value through a procedure that is also known
as programming.
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7.1.1. Configuration Variables (CV)

All SwitchPilot decoders follow the CV concept which was deve-
loped in the United States. The name CV (Configuration Variable)
is derived from the fact that the memory cells being described
above are not only variable but can also configure the behavior
of the decoder.

7.1.1.1. Standardization regarding NMRA

The NMRA (National Model Railroad Association) has specified
which CV controls what function in a decoder. The DCC norm
describes the CVs with numbers whereby the most important ones
are given. Thereby the handling of CVs is simplified for the user
since decoders of many manufacturers follow this standardizati-
on and the learned handling of CVs can be applied everywhere.
Within the DCC CV concept number values between 0 and 255
can be written into CVs. Each CV consists of exactly one number.
While the position (CV number) has been predetermined the ac-
tual range of values can vary. Not all CVs need to accept values
between 0 and 255. Allowed values for the SwitchPilot decoder
are shown in the list in Chapter 20.

7.1.1.2. Bits und Bytes

Most CVs contain numerical values: CV 8 for example contains the
manufacturer's identification. This one can range from 1 to 255.
Other CVs can be understood as a collection point of different
switches which together control different functions (most often
turning on or off). Good examples are CVs 28 and 29: The inten-
ded value for this CV needs to be calculated. This value depends
on the desired parameter. Take a look at the table in Chapter 17
and its description for CV34: First decide which option needs to
be turned on or off. In the value column are two numbers for each
option. If the option is turned off the value is set 0, otherwise a
number between 1 and 8. Add those two numerical values for
this specific option and you will get the value which needs to be
written into the CV.