Specifications

MICROPROCESSADORES
CONJUNTO DE INSTRUÇÕES DO 8086
4
Luís Miguel Charrua Figueiredo 4 - 8 E.N.I.D.H.
Stores value in accumulator to location at ES:(E)DI (even
if operand is given). (E)DI is incremented/decremented
based on the size of the operand (or instruction format)
and the state of the Direction Flag. Use with REP
prefixes.
SUB - Subtract
Usage: SUB dest,src
Modifies flags: AF CF OF PF SF ZF
The source is subtracted from the destination and the
result is stored in the destination.
TEST - Test For Bit Pattern
Usage: TEST dest,src
Modifies flags: CF OF PF SF ZF (AF undefined)
Performs a logical AND of the two operands updating the
flags register without saving the result.
WAIT/FWAIT - Event Wait
Usage: WAIT
FWAIT
Modifies flags: None
CPU enters wait state until the coprocessor signals it has
finished its operation. This instruction is used to prevent
the CPU from accessing memory that may be temporarily
in use by the coprocessor. WAIT and FWAIT are identical.
XCHG - Exchange
Usage: XCHG dest,src
Modifies flags: None
Exchanges contents of source and destination.
XLAT/XLATB - Translate
Usage: XLAT translation-table
XLATB (masm 5.x)
Modifies flags: None
Replaces the byte in AL with byte from a user table
addressed by BX. The original value of AL is the index
into the translate table. The best way to discripe this is
MOV AL,[BX+AL]
XOR - Exclusive OR
Usage: XOR dest,src
Modifies flags: CF OF PF SF ZF (AF undefined)
Performs a bitwise exclusive OR of the operands and
returns the result in the destination.