n---------------m
| n----------m | n--m
v->|7------->0|-T->|CY|
v----------u v--u
(IY+d)
RR
(IY+d)
| b7 | b6 | b5 | b4 | b3 | b2 | b1 | b0 | |
|---|---|---|---|---|---|---|---|---|
| 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | $FD |
| 1 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | $CB |
| d | ||||||||
| 0 | 0 | 0 | 1 | 1 | 1 | 1 | 0 | $1E |
The contents of the memory address specified by the sum of the contents of Index Register IY and the two's-complement displacement integer, d, are rotated right 1 bit position through the Carry flag. The contents of bit 0 are copied to the Carry flag and the previous contents of the Carry flag are copied to bit 7.
| S | is set if result is negative, otherwise it is reset. |
| Z | is set if result is 0, otherwise it is reset. |
| H | is reset. |
| P/V | is set if parity even, otherwise it is reset |
| N | is reset. |
| C | is data from bit 0 of source register. |
Index Register IX contains $1000 and the contents of memory location $1002 are:
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | C | |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 1 | 0 | 1 | 1 | 1 | 0 | 1 | 0 |
Upon the execution of
RR (IY+$2)
memory location $1002 and the Carry flag now contain:
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | C | |
|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 1 | 0 | 1 | 1 | 1 | 0 | 1 |