Intel 80286

PROGRAMMING NUMERIC APPLICATIONS
Table 2-14. Instruction Set Reference Data (Cont'd.)
FSUBR
FSUBR / /source/destination, source
Exceptions:
I, D, 0, U, P
Subtract real reversed
Execution Clocks
Operands
Operand Word Code
Coding Example
Typical Range
Transfers Bytes
/ /ST,ST(i)/ST(i),ST
87 70-100 0 2 FSUBR ST,ST(1)
short-real
105
90-120 2 2-4
FSUBR VECTOR[SI]
long-real 110 95-125 4 2-4 FSUBR [BX].INDEX
FSUBRP
FSUBRP destination, source
Exceptions:
I, D, 0, U, P
Subtract real reversed and pop
Execution Clocks
Operands
Operand Word
Code
Coding Example
Typical Range
Transfers
Bytes
ST(i),ST
90 75-105 0 2
FSUBRP ST(1),ST
FTST FTST (no operands)
Exceptions:
I, D
Test stack top against
+0.0
Execution Clocks
Operands
Operand Word
Code
Coding Example
Typical Range
Transfers Bytes
(no operands)
42 38-48
0 2 FTST
FWAIT FWAIT (no operands)
Exceptions: None
(CPU instruction)
(CPU) Wait while 80287
is busy
Execution Clocks
Operands
Operand Word
Coda
Coding Example
Typical
Range
Transfers
Bytes
(no operands)
3+5n* 3+5n
4
0 1 FWAIT
FXAM FXAM (no operands)
Exceptions: None
Examine stack top
Execution Clocks
Operands
Operand Word Code
Coding Example
Typical Range
Transfers Bytes
(no operands)
17 12-23
0
2 FXAM
2-36
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