fstsw

Store Status Word

FSTSW AX

Stores FPU status word to AX or memory.

Details

The Store Status Word instruction stores FPU status word to AX or memory.

Pseudocode Operation

// Stores FPU status word to AX or memory

Example

FSTSW AX

Encoding

Binary Layout
9B
+0
DF
+1
E0
+2
 
Format Legacy
Opcode 9B DF E0
Extension x87 FPU

Operands

  • dest
    AX/Mem