M166 Datasheet, PDF (55/127 Pages) Siemens Semiconductor Group – C16x Family of Siemens 16-Bit CMOS Single-Chip Microcontrollers

30Mar98@15:00h
C166 Family Instruction Set
Instruction Description
CMPB
Integer Compare
CMPB
Syntax
Operation
Data Types
Description
CMPB op1, op2
(op1) ⇔ (op2)
BYTE
The source operand specified by op1 is compared to the source operand
specified by op2 by performing a 2’s complement binary subtraction of
op2 from op1. The flags are set according to the rules of subtraction. The
operands remain unchanged.
Condition Flags
E
Z
V
C
N
*
*
*
S
*
Addressing Modes
E Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Z Set if result equals zero. Cleared otherwise.
V Set if an arithmetic underflow occurred, ie. the result cannot be repre-
sented in the specified data type. Cleared otherwise.
C Set if a borrow is generated. Cleared otherwise.
N Set if the most significant bit of the result is set. Cleared otherwise.
Mnemonic
CMPB
CMPB
CMPB
CMPB
CMPB
Rb_n, Rb_m
Rb_n, [Rw_i]
Rb_n, [Rw_i+]
Rb_n, #data3
reg, #data16
CMPB reg, mem
Format
41 nm
49 n:10ii
49 n:11ii
49 n:0###
47 RR ## xx
43 RR MM MM
Bytes
2
2
2
2
4
4
Semiconductor Group
55
Version 1.2, 12.97