INSTRUCTION SET S3F80P5_UM_ REV1.00
INC — Increment
INC dst
Operation: dst ← dst + 1
The contents of the destination operand are incremented by one.
Flags: C: Unaffected.
Z: Set if the result is "0"; cleared otherwise.
S: Set if the result is negative; cleared otherwise.
V: Set if arithmetic overflow occurred; cleared otherwise.
D: Unaffected.
H: Unaffected.
Format:
Bytes Cycles Opcode
(Hex) Addr Mode
dst
dst | opc 1 4 rE r
r = 0 to F
opc dst
2 4 20 R
4 21 IR
Examples: Given: R0 = 1BH, register 00H = 0CH, and register 1BH = 0FH:
INC R0 → R0 = 1CH
INC 00H → Register 00H = 0DH
INC @R0 → R0 = 1BH, register 01H = 10H
In the first example, if destination working register R0 contains the value 1BH, the statement "INC
R0" leaves the value 1CH in that same register.
The next example shows the effect an INC instruction has on register 00H, assuming that it
contains the value 0CH.
In the third example, INC is used in Indirect Register (IR) addressing mode to increment the
value of register 1BH from 0FH to 10H.
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