User's Manual

THE 80286 INSTRUCTION SET
POPF-Pop from Stack into the Flags Register
Opcode Instruction Clocks Description
9D POPF 5 Pop top of stack into flags register
FLAGS MODIFIED
Entire flags register is popped from stack
FLAGS UNDEFINED
None
OPERATION
The top of the 80286 stack, pointed to by SS:SP, is copied into the 80286 flags register. The stack
pointer
SP is incremented by 2to point to the new top of stack. The flags, from the top bit (bit 15) to
the bottom (bit 0), are as follows: undefined, nested task, I/O privilege level (2 bits), overflow, direc-
tion, interrupts enabled, trap, sign, zero, undefined, auxiliary carry, undefined, parity, undefined, and
carry.
The
I/O privilege level will be altered only when executing at privilege level O. The interrupt enable
flag
will be altered only whim executing at a level at least as privileged as the I/O privilege level. If
you execute a POPF instruction with insufficient privilege, there will be no exception nor will the
privileged bits
be changed.
PROTECTED MODE EXCEPTIONS
#SS(O).if the top of stack is not within the stack segment.
REAL ADDRESS MODE EXCEPTIONS
Interrupt 13 for a word operand at OFFFFH.
In real mode the
NT and 10PL bits will not be modified.
8-86