THE 80286 INSTRUCTION SET

INC-Increment by 1

Opcode

Instruction

Clocks

Description

FE

/0

INC eb

2,mem=7

Increment EA byte by 1

FF

/0

"INC

ew

2,mem=7

Increment EA word by 1

40+rw

INC

rw

2

Increment word register by 1

FLAGS MODIFIED

Overflow, sign, zero, auxiliary carry, parity

FLAGS UNDEFINED

None

OPERATION

1 is added to the operand. Note that the carry flag is not changed by this instruction. If you want the carry flag;set, use the ADD instruction with a second operand of 1.

PROTECTED MODE EXCEPTIONS

#GP(O) if the operand is in a non-writable segment. #GP(O) for an illegal memory operand effective address in the CS! DS, or ES segments; #SS(O) for an illegal address in the SS segment.

REAL ADDRESS MODE EXCEPTIONS

Interrupt 13 for a word operand at offset OFFFFH.

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Intel 80287, 80286 manual Mem=7 Increment EA word by