CMOS.layout guide

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CMOS.layout

This page explain the workings of the CMOS.layout file. The CMOS.layout file can be linked into a board specific environment. By creating the cmos.layout file in the board directory. and set the HAVE_OPTION_TABLE in the Kconfig file of the board.

The CMOS layout file must contain the following sections;

  • entries
  • enumerations
  • checksums

entries section

enumerations section

checksums section

The checksums section has one variable with three parameters;

 checksum <startbit> <endbit> <start-of-checksumbit>

The <startbit> parameter is the bit position where the calculation of the checksum starts from.

The <endbit> parameter is the bit position there the calculation of the checksum starts on.

The <start-of-checksumbit> parameter is the bit position there the checksum will be stored, there must be space for 16 bits of checksum data.

Example;

 checksum 392 983 984