Data rotate            index 03h  GRAPH

Layout  b5-b4  FS   Function select
        b3-b0  RC   Rotate count

- Function select (bits 5-4)
        Data written from the host to the display memory may be
        logically modified with data already present in the display
        memory. The logical function selected is determined by the
        value in this field.

                b5 b4  Function
                0  0   Data is written unmodified
                0  1   Data is ANDed with latched data
                1  0   Data is ORed with latched data
                1  1   Data is XORed with latched data

- Rotate count (bits 3-0)
        Data written from the host to the display memory will be
        rotated to the right the number of bits indicated in this
        field. This rotation will occur before any other logical
        operations happen to this data on its way to the display
        memory.