Intel 80287 User Manual

NUMERIC PROGRAMMING EXAMPLES
ASSUME INITIALIZED
REENTRANT PROC
SAVE CPU REGISTERS, ALLOCATE STACK SPACE FOR
80287 STATE IMAGE
PUSH BP
MOV BP,SP
SUB SP,94
SAVE STATE, LOAD NEW CONTROL WORD,
FOR COMPLETION, ENABLE CPU INTERRUPTS
FNSAVE [BP-941
FLDCW LOCAL_CONTROL
S T I
APPLICATION EXCEPTION HANDLING CODE GOES HERE.
AN UNMASKED EXCEPTION GENERATED HERE WILL
CAUSE THE EXCEPTION HANDLER TO BE REENTERED.
IF LOCAL STORAGE IS NEEDED, IT MUST BE
ALLOCATED ON THE CPU STACK.
CLEAR EXCEPTION FLAGS IN STATUS WORD
RESTORE MODIFIED STATE IMAGE
MOV BVTE PTR [BP-921, OH
FRSTOR [BP-941
DE-ALLOCATE STACK SPACE, RESTORE CPU REGISTERS
MOV SP,BP
POP BP
RETURN POINT OF INTERRUPTIOH
IRET
REENTRANT ENDP
Figure 4-5. Reentrant Exception Handler
4-6
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Intel 80287 Specifications

General

Brand	Intel
Model	80287
Category	Computer Hardware
Language	English