|
| |
| Processor
Flags |
| 31 |
30 |
29 |
28 |
27 |
26 |
25 |
24 |
23 |
22 |
21 |
20 |
19 |
18 |
17 |
16 |
| 0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
VM |
RF |
| 15 |
14 |
13
12 |
11 |
10 |
9 |
8 |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0 |
| 0 |
NT |
IOPL |
OF |
DF |
IF |
TF |
SF |
ZF |
0 |
AF |
0 |
PF |
1 |
CF |
CF Carry Flag
Set to 1 if an arithmetic operation generates a carry or
borrow out of the most significant bit, otherwise it is
cleared.
PF Parity Flag
Indicates the parity of the lower 8 bits of the result.
PF is 1 if there are an even number of 1s in the lower 8
bits of the result, and a 0 if there are an odd number
of 1s.
AF Auxiliary Carry Flag
Set if thre is a carry or borrow out of bit 3. It is used
in performing BCD arithmetic.
ZF Zero Flag
Set if the result is zero.
SF Sign Flag
Set to the most significant bit of the result, which is
the sign bit in two's complement notation.
TF Trap Enable Flag
Controls the generation of single step interrupts to
support program debugging.
IF Interrupt Enable Flag
Enables the recognition of external interrupts signaled
on a processor pin.
DF Direction Flag
Determines whether string instructions will post-
increment or post-decrement the string index register.
OF Overflow Flag
Set if the result of an arithmetic operation is too large
or too small to be represented as a two's complement
integer in the number of bits available to store the
result.
IOPL I/O Priviledge Level
Sets the current I/O Priviledge Level.
NT Nested Task Flag
Controls the operation of the IRET instruction. If this
flag is set, control is returned through a task switch.
RF Restart Flag
Controls whether debug faults are accepted or ignored.
VM Virtual 8086 Mode Flag
Controls whether the processor operates in Virtual 8086
mode. |
