SAB80515 Datasheet, PDF (160/270 Pages) Siemens Semiconductor Group – 8-Bit Single-Chip Microcontroller Family

Instruction Set
INC
<byte>
Function:
Increment
Description:
INC increments the indicated variable by 1. An original value of 0FFH will overflow
to 00H. No flags are affected. Three addressing modes are allowed: register, direct,
or register-indirect.
Example:
Note:
When this instruction is used to modify an output port, the value used as the original
port data will be read from the output data latch, not the input pins.
Register 0 contains 7EH (01111110B). Internal RAM locations 7EH and 7FH
contain 0FFH and 40H, respectively. The instruction sequence
INC
@R0
INC
R0
INC
@R0
will leave register 0 set to 7FH and internal RAM locations 7EH and 7FH holding
(respectively) 00H and 41H.
INC
A
Operation:
INC
(A) ← (A) + 1
Encoding:
Bytes:
Cycles:
0000 0100
1
1
INC
Rn
Operation:
INC
(Rn) ← (Rn) + 1
Encoding:
Bytes:
Cycles:
0000 1rrr
1
1
Semiconductor Group
160