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Copy pathOdeToEflags
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OdeToEflags
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Bit mapping of eflags register.
Bit no. Nmemonic Elaboration Status & Description
------- -------- ----------- --------------------
0 CF Carry Flag 0=No Carry, 1=Carry.
1 N/A Yet to be defined. Always 1 in eflags.
2 PF Parity Flag 1=Even Parity, 0=Odd Parity.
3 N/A Yet to be defined. N/A
4 AF Auxilary Carry Flag Indicates carry in BCD operation. 0=No BCD Carry, 1=BCD Carry.
5 N/A Yet to be defined. N/A
6 ZF Zero Flag 0=Operand didn't become 0, 1=Operand became zero.
7 SF Sign Flag 0=Operand didn't become -ve, 1=Operand became -ve.
8 TF Trap Flag Fascilitates single stepping like those done inside debugger.
9 IF Interrupt Enable Flag Reserved by OS.
10 DF Direction Flag 0=Autoincrement towards down memory, 1=Autoincrement towards up memory.
11 OF Overflow Flag 0=Overflow in signed operation, 1=Overflow didn't occur in signed operation.
12 IOPL I/O previledge level 0 Reserved by OS.
13 IOPL I/O previledge level 1 Reserved by OS.
14 NT Nested Task flag Reserved by OS.
15 N/A Yet to be defined. N/A
16 RF Resume Flag. Evil twin of Trap Flag. signals trapped single step resuming.
17 VM Virtual 8086 mode flag Reserved by OS.
18 AC Alignment check flag Reserved by OS.
19 VIF Virtual Interrupt flag Reserved by OS.
20 VIP Virtual Interrupt pending Reserved by OS.
21 ID CPU ID If this bit can be changed by user space program, CPUID is available.
22 to 63 N/a Yet to be defined. N/A