Intel 80286

PROGRAMMING NUMERIC APPLICATIONS
Table 2-14. Instruction Set Reference Data (Cont'd.)
FCHS FCHS (no operands)
Exceptions: I
Change sign
Execution Clocks
Operands
Operand Word Code
Coding Example
Typical
Range
Transfers
Bytes
(no operands)
15 10-17
0
2 FCHS
FClEX/FNClEX FClEX/FNClEX(no operands)
Exceptions: None
Clear exceptions
Execution Clocks
Operands
Operand Word Code
Coding Example
Typical Range
Transfers
Bytes
(no operands) 5
2-8
0
2
FNCLEX
FCOM
FCOM j jsource
Exceptions:
I, D
Compare real
Execution Clocks
Operands
Operand Word
Code
Coding Example
Typical
Range
Transfers
Bytes
jjST(i)
45 40-50
0
2 FCOM ST(1)
short-real
65 60-70 2 2-4
FCOM [BP].UPPER_LlMIT
long-real 70 65-75 4
2-4 FCOM WAVELENGTH
FCOMP FCOMP j jsource
Exceptions:
I, D
Compare real and pop
Execution Clocks
Operands
Operand Word Code
Coding Example
Typical
Range
Transfers
Bytes
jjST(i)
47 42-52 0 2
FCOMP ST(2)
short-real
68 63-73 2
2-4 FCOMP [BP
+ 2].N_READINGS
long-real
72
67-77 4 2-4 FCOMP DENSITY
FCOMPP FCOMPP (no operands)
Exceptions:
I, D
Compare real and pop twice
Execution Clocks
Operands
Operand Word
Code
Coding Example
Typical Range
Transfers Bytes
(no operands)
50
45-55
0
2 FCOMPP
2-25
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