S3C80M4 Datasheet, PDF (174/248 Pages) Samsung semiconductor – 8-BIT CMOS MICROCONTROLLERS USERS MANUAL

INSTRUCTION SET
S3C80M4/F80M4
RLC — Rotate Left Through Carry
RLC
dst
Operation:
dst (0) ← C
C ← dst (7)
dst (n + 1) ← dst (n), n = 0–6
The contents of the destination operand with the carry flag are rotated left one bit position. The
initial value of bit 7 replaces the carry flag (C); the initial value of the carry flag replaces bit zero.
Flags:
Format:
7
0
C
C: Set if the bit rotated from the most significant bit position (bit 7) was "1".
Z: Set if the result is "0"; cleared otherwise.
S: Set if the result bit 7 is set; cleared otherwise.
V: Set if arithmetic overflow occurred, that is, if the sign of the destination changed during
rotation; cleared otherwise.
D: Unaffected.
H: Unaffected.
opc
dst
Bytes
2
Cycles
4
4
Opcode
(Hex)
10
11
Addr Mode
dst
R
IR
Examples:
Given: Register 00H = 0AAH, register 01H = 02H, and register 02H = 17H, C = "0":
RLC
RLC
00H
@01H
→
Register 00H = 54H, C = "1"
→
Register 01H = 02H, register 02H = 2EH, C = "0"
In the first example, if general register 00H has the value 0AAH (10101010B), the statement
"RLC 00H" rotates 0AAH one bit position to the left. The initial value of bit 7 sets the carry flag
and the initial value of the C flag replaces bit zero of register 00H, leaving the value 55H
(01010101B). The MSB of register 00H resets the carry flag to "1" and sets the overflow flag.
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