80C186EB/80C188EB, 80L186EB/80L188EB
INSTRUCTION SET SUMMARY
(Continued)
80C186EB
80C188EB
Function
Format
Clock
Clock
Comments
Cycles
Cycles
PROCESSOR CONTROL
CLC
e
Clear carry
1 1 1 1 1 0 0 0
2
2
CMC
e
Complement carry
1 1 1 1 0 1 0 1
2
2
STC
e
Set carry
1 1 1 1 1 0 0 1
2
2
CLD
e
Clear direction
1 1 1 1 1 1 0 0
2
2
STD
e
Set direction
1 1 1 1 1 1 0 1
2
2
CLI
e
Clear interrupt
1 1 1 1 1 0 1 0
2
2
STI
e
Set interrupt
1 1 1 1 1 0 1 1
2
2
HLT
e
Halt
1 1 1 1 0 1 0 0
2
2
WAIT
e
Wait
1 0 0 1 1 0 1 1
6
6
if TEST
e
0
LOCK
e
Bus lock prefix
1 1 1 1 0 0 0 0
2
2
NOP
e
No Operation
1 0 0 1 0 0 0 0
3
3
(TTT LLL are opcode to processor extension)
Shaded areas indicate instructions not available in 8086/8088 microsystems.
NOTE:
*
Clock cycles shown for byte transfers. For word operations, add 4 clock cycles for all memory transfers.
FOOTNOTES
The Effective Address (EA) of the memory operand
is computed according to the mod and r/m fields:
if mod
e
11 then r/m is treated as a REG field
if mod
e
00 then DISP
e
0
*
, disp-low and disp-
high are absent
if mod
e
01 then DISP
e
disp-low sign-ex-
tended to 16-bits, disp-high is absent
if mod
e
10 then DISP
e
disp-high: disp-low
if r/m
e
000 then EA
e
(BX)
a
(SI)
a
DISP
if r/m
e
001 then EA
e
(BX)
a
(DI)
a
DISP
if r/m
e
010 then EA
e
(BP)
a
(SI)
a
DISP
if r/m
e
011 then EA
e
(BP)
a
(DI)
a
DISP
if r/m
e
100 then EA
e
(SI)
a
DISP
if r/m
e
101 then EA
e
(DI)
a
DISP
if r/m
e
110 then EA
e
(BP)
a
DISP
*
if r/m
e
111 then EA
e
(BX)
a
DISP
DISP follows 2nd byte of instruction (before data if
required)
*
except if mod
e
00 and r/m
e
110 then EA
e
disp-high: disp-low.
EA calculation time is 4 clock cycles for all modes,
and is included in the execution times given whenev-
er appropriate.
Segment Override Prefix
0
0
1
reg
1
1
0
reg is assigned according to the following:
Segment
reg
Register
00
ES
01
CS
10
SS
11
DS
REG is assigned according to the following table:
16-Bit (w
e
1)
8-Bit (w
e
0)
000 AX
000 AL
001 CX
001 CL
010 DX
010 DL
011 BX
011 BL
100 SP
100 AH
101 BP
101 CH
110 SI
110 DH
111 DI
111 BH
The physical addresses of all operands addressed
by the BP register are computed using the SS seg-
ment register. The physical addresses of the desti-
nation operands of the string primitive operations
(those addressed by the DI register) are computed
using the ES segment, which may not be overridden.
58