INSTRUCTION SET OPCODES AND CLOCK CYCLES

Table D-2. Instruction Set Summary (Continued)

Function

 

Format

Clocks

Notes

 

 

 

 

 

 

PROCESSOR CONTROL INSTRUCTIONS

 

 

CLC = Clear carry

 

 

 

 

 

1 1 1 1 1 0 0 0

 

 

2

 

CMC = Complement carry

 

 

 

 

 

1 1 1 1 0 1 0 1

 

 

2

 

STC = Set carry

 

 

 

 

 

1 1 1 1 1 0 0 1

 

 

2

 

CLD = Clear direction

 

 

 

 

 

1 1 1 1 1 1 0 0

 

 

2

 

STD = Set direction

 

 

 

 

 

1 1 1 1 1 1 0 1

 

 

2

 

CLI = Clear interrupt

 

 

 

 

 

1 1 1 1 1 0 1 0

 

 

2

 

STI = Set interrupt

 

 

 

 

 

1 1 1 1 1 0 1 1

 

 

2

 

HLT = Halt

 

 

 

 

 

1 1 1 1 0 1 0 0

 

 

2

 

WAIT = Wait

 

 

 

 

 

1 0 0 1 1 0 1 1

 

 

6

(4)

LOCK = Bus lock prefix

 

 

 

 

 

1 1 1 1 0 0 0 0

 

 

2

 

ESC = Math coprocessor escape

 

 

 

 

1 1 0 1 1 M M M

mod PPP r/m

 

6

 

NOP = No operation

 

 

 

 

 

1 0 0 1 0 0 0 0

 

 

3

 

SEGMENT OVERRIDE PREFIX

 

 

 

 

 

 

 

 

 

 

CS

 

 

 

 

 

0 0 1 0 1 1 1 0

 

 

2

 

SS

 

 

 

 

 

0 0 1 1 0 1 1 0

 

 

2

 

DS

 

 

 

 

 

0 0 1 1 1 1 1 0

 

 

2

 

ES

 

 

 

 

 

0 0 1 0 0 1 1 0

 

 

2

 

 

 

 

 

 

 

 

 

 

 

 

 

NOTES:

1.Clock cycles are given for 8-bit/16-bit operations.

2.Clock cycles are given for jump not taken/jump taken.

3.Clock cycles are given for interrupt taken/interrupt not taken.

4.If TEST = 0

Shading indicates additions and enhancements to the 8086/8088 instruction set. See Appendix A, “80C186 Instruction Set Additions and Extensions,” for details.

Table D-3. Machine Instruction Decoding Guide

 

Byte 1

Byte 2

Bytes 3–6

 

ASM-86 Instruction Format

 

 

 

Hex

Binary

 

 

 

 

 

 

 

 

 

 

 

00

0000 0000

mod reg r/m

(disp-lo),(disp-hi)

add

reg8/mem8, reg8

 

 

 

 

 

 

01

0000 0001

mod reg r/m

(disp-lo),(disp-hi)

add

reg16/mem16,reg16

 

 

 

 

 

 

02

0000 0010

mod reg r/m

(disp-lo),(disp-hi)

add

reg8,reg8/mem8

 

 

 

 

 

 

03

0000 0011

mod reg r/m

(disp-lo),(disp-hi)

add

reg16,reg16/mem16

 

 

 

 

 

 

04

0000 0100

data-8

 

add

AL,immed8

 

 

 

 

 

 

05

0000 0101

data-lo

data-hi

add

AX,immed16

 

 

 

 

 

 

06

0000 0110

 

 

push

ES

 

 

 

 

 

 

07

0000 0111

 

 

pop

ES

 

 

 

 

 

 

08

0000 0100

mod reg r/m

(disp-lo),(disp-hi)

or

reg8/mem8,reg8

 

 

 

 

 

 

D-9

Page 382
Image 382
Intel 80C188XL, 80C186XL user manual Table D-3. Machine Instruction Decoding Guide, Processor Control Instructions