NEC 78K/0 Series User Manual page 81

ROL4
[Instruction format]
[Operation]
[Operand]
Mnemonic
ROL4 [HL]
Note Specify an area other than the SFR area as operand [HL].
[Flag]
Z AC
[Description]
• The lower 4 bits of the A register and the 2-digit data (4-bit data) of the destination operand (dst) are rotated
to the left.
The higher 4 bits of the A register remain unchanged.
A
[Description example]
ROL4 [HL]; Leftward digit rotation is executed with the memory contents specified by the A and HL registers.
Before Execution
After Execution
CHAPTER 5 EXPLANATION OF INSTRUCTIONS
ROL4 dst
← (dst) ← A
A , (dst)
3-0 7-4 3-0
Operand(dst)
Note
CY
7 4 3 0
A
7 4
0001
0001
User's Manual U12326EJ4V0UM
← (dst)
, (dst)
3-0 7-4 3-0
7 4 3
dst
(HL)
3 0 7 4 3
0010 0100 1000
0100 1000 0010
Rotate Left Digit
Digit Rotation to the Left
0
0
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