Intel 80C188XL, 80C186XL user manual Table C-3. Flag Bit Functions

INSTRUCTION SET DESCRIPTIONS

	Table C-3. Flag Bit Functions
Name	Function
AF	Auxiliary Flag:
	Set on carry from or borrow to the low order four bits of AL; cleared otherwise.
CF	Carry Flag:
	Set on high-order bit carry or borrow; cleared otherwise.
DF	Direction Flag:
	Causes string instructions to auto decrement the appropriate index register
	when set. Clearing DF causes auto increment.
IF	Interrupt-enable Flag:
	When set, maskable interrupts will cause the CPU to transfer control to an
	interrupt vector specified location.
OF	Overflow Flag:
	Set if the signed result cannot be expressed within the number of bits in the
	destination operand; cleared otherwise.
PF	Parity Flag:
	Set if low-order 8 bits of result contain an even number of 1 bits; cleared
	otherwise.
SF	Sign Flag:
	Set equal to high-order bit of result (0 if positive, 1 if negative).
TF	Single Step Flag:
	Once set, a single step interrupt occurs after the next instruction executes. TF
	is cleared by the single step interrupt.
ZF	Zero Flag:
	Set if result is zero; cleared otherwise.

C-3