INSTRUCTION SET DESCRIPTIONS

Table C-4. Instruction Set (Continued)

Name

Description

Operation

Flags

Affected

 

 

 

 

 

 

 

OR

Logical OR:

(dest) (dest) or (src)

AF ?

 

OR dest,src

(CF) 0

CF

 

(OF) 0

DF –

 

Performs the logical "inclusive or" of

 

 

IF –

 

the two operands (bytes or words) and

 

 

 

OF

 

returns the result to the destination

 

 

 

PF

 

operand. A bit in the result is set if

 

 

 

SF

 

either or both corresponding bits in the

 

 

 

TF –

 

original operands are set; otherwise

 

 

 

ZF ¸

 

the result bit is cleared.

 

 

 

Instruction Operands:

 

 

 

OR reg, reg

 

 

 

OR reg, mem

 

 

 

OR mem, reg

 

 

 

OR accum, immed

 

 

 

OR reg, immed

 

 

 

OR mem, immed

 

 

 

 

 

 

OUT

Output:

(dest) (src)

AF –

 

OUT port, accumulator

 

CF –

 

 

DF –

 

Transfers a byte or a word from the AL

 

 

 

IF –

 

register or the AX register, respec-

 

 

 

OF –

 

tively, to an output port. The port

 

 

 

PF –

 

number may be specified either with

 

 

 

SF –

 

an immediate byte constant, allowing

 

 

 

TF –

 

access to ports numbered 0 through

 

 

 

ZF –

 

255, or with a number previously

 

 

 

 

 

placed in register DX, allowing variable

 

 

 

access (by changing the value in DX)

 

 

 

to ports numbered from 0 through

 

 

 

65,535.

 

 

 

Instruction Operands:

 

 

 

OUT immed8, AL

 

 

 

OUT DX, AX

 

 

 

 

 

 

NOTE: The three symbols used in the Flags Affected column are defined as follows:

the contents of the flag remain unchanged after the instruction is executed ¸? the contents of the flag is undefined after the instruction is executed

the flag is updated after the instruction is executed

C-32

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Intel 80C186XL, 80C188XL Name Description Operation Flags Affected Logical or, Or dest,src, Output, OUT port, accumulator