Rabbit 2000, Reference Manual

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82 Rabbit 2000/3000 Microprocessor
Description
Rotates to the left with the Carry Flag, CF, the data whose address is:
• the data in word register HL, or
• the sum of the data in index register IX and a displacement d, or
• the sum of the data in index register IY and a displacement d.
Bits 0 through 6 move to the next highest-order bit position (bit 0 moves to bit 1, etc.) while the CF moves to
bit 0 and bit 7 moves to the CF. See Figure 1 below.
Example
If the HL contains 0x4545, the byte in the memory location 0x4545 is 0110 1010, and the CF is set, then after
the execution of the operation
RL (HL)
The byte in memory location 0x4545 will contain 1101 0101 and the CF will be reset.
RL (HL)
RL (IX+d)
RL (IY+d)
Opcode Instruction Clocks Operation
CB 16 RL (HL) 10 (2,2,1,2,3) {CF,(HL)} = {(HL),CF}
DD CB d 16 RL (IX+d) 13 (2,2,2,2,2,3) {CF,(IX + d)} = {(IX + d),CF}
FD CB d 16 RL (IY+d) 13 (2,2,2,2,2,3) {CF,(IY + d)} = {(IY + d),CF}
Flags ALTD I/O
S Z L/V C F R SP S D
• • L • • • •
Figure 1: The bit logic of the RL instruction.
CF
7
0