Value Evaluation Rules
Value evaluation rules define the outcome of the write operations performed
by the = command to registers that exist.
Value-Mapped
Value-mapped register values have bounds. Write commands with values
that are within the bounds are accepted. If an attempt is made to write
a value that is outside of the allowed range, then the outcome is (1) below
unless (2) is specified in the register description.
1. The bound value that is closest to the entered value is written and an
OK result code returned.
2. The register value is not changed and the ERROR result code is returned.
Bit-Mapped
The bits to write to a bit-mapped register are determined from the binary
number equivalent to the decimal value entered in a write command. Bits
indicated by the value that are defined are written. Unused bits indicated
by the value are ignored and their values set to 0. For example, if the
value 10 is given in a write command (binary 1010) to a register for which
only bits 0, 1, and 2 are used, then bits 0, 1, and 2 are set to 0, 1, and
0, respectively, and all other bits set to 0.
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