In an example embodiment, a method writes individual bits of data to a
register. Bits of data are received in a data field. The number of bits
in the data field is equal to the number of bits in the register and the
bit locations in the data field correspond respectively to the bit
locations in the register. Enable bits are received in a bit enable
field. The number of enable bits in the bit enable field is equal to the
number of bits in the register. The bit locations in the bit enable field
correspond respectively to bit locations in the register. Only the bits
at the bit locations of the register for which the enable bit in the
corresponding location in the bit enable field is set are overwritten
with the bit in the corresponding location in the data field.