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11 cmpb compare two bytes – Texas Instruments MSP50C6xx User Manual

Page 179

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Individual Instruction Descriptions

4-93

Assembly Language Instructions

4.14.11

CMPB

Compare Two Bytes

Syntax

[label]

name

src, src1

Clock, clk

Word, w

With RPT, clk

Class

CMPB

An, imm8

1

1

N/R

2a

CMPB

Rx, imm8

1

1

N/R

4b

Execution

status flags set by srcsrc1 byte
PC

PC + 1

Flags Affected

src is An:

OF, SF, ZF, CF are set accordingly

src is Rx:

RCF, RZF are set accordingly

Opcode

Instructions

16

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

CMPB An, imm8

1

0

1

0

0

1

1

An

imm8

CMPB Rx, imm8

1

0

1

1

1

1

k4

k3

k2

k7

k6

k5

Rx

k1

k0

Description

Subtract value of src1 (zero filled in upper 8 bits) from src (i.e., srcsrc1) and
only modify the status flags. Contents of src not changed.

See Also

CMP, CMPS, Jcc, Ccc

Example 4.14.11.1

CMPB A0, 0xf3

Compare immediate value 0xf3 to accumulator A0.

Example 4.14.11.2

CMPB R3, 0x21

Compare immediate value 0x21 to R3.