4
FACOS
Arc Cosine
FACOS
Operation:
Arc Cosine of Source @ FPn
Assembler
FACOS.<fmt> <ea>,FPn
Syntax:
FACOS.X FPm,FPn
FACOS.X FPn
Attributes:
Format = (Byte, Word, Long, Single, Double, Extended, Packed)
Description:
Converts the source operand to extended precision (if necessary) and cal-
culates the arc cosine of that number. Stores the result in the destination floating-
point data register. This function is not defined for source operands outside of the
range [- 1 ... + 1]; if the source is not in the correct range, a NAN is returned as the
result and the OPERR bit is set in the FPSR. If the source is in the correct range, the
result is in the range of [0... ~r].
Operation
Table:
e
In
Range
Result Arc Cosine
Zero
Infinity
+ - +
- = 2 { NAN ]
NOTES:
1. Sets the OPERR bit in the FPSR exception byte.
2. If the source operand is a NAN, refer to 4.5.4 NANs for more information.
Status Register:
Condition Codes:
Quotient Byte:
Exception Byte:
Accrued Exception Byte:
Instruction Format:
15 14 13
1 ! 1
0 R/M 0
Affected as described in 4.5.5.1 SETTING FLOATING-POINT
CONDITION
CODES.
Not affected
BSUN
SNAN
OPERR
OVFL
UNFL
DZ
INEX2
INEX1
Cleared
Refer to 4,5.4
NANs.
Set if the source is infinity, > -1 or < -1;
cleared otherwise.
Cleared
Cleared
Cleared
Refer to 6.1.7
Inexact Result.
If <fmt> is Packed, refer to 6.1.8 Inexact Result
on Decimal
Input; cleared otherwise.
Affected as described in 6.1.10 IEEE Exception and Trap Com-
patibility.
12 11 l0 9 8 7
O 0
COPROCESSOR
1 LD
SOURCE
]
DESTINATION
SPECIFIER REGISTER
6 5 4 3 2 1 O
I EFFECTIVE ADDRESS ;
O MODE {
REGISTER
0101
FREESCALE
4-20
MC68881/MC68882 USER'S MANUAL
To Next Page
Loading...