4
FSQRT
Square Root
FSQRT
Instruction Format:
15 14 13 t2 11 l0 9 8 7
COPROCESSOR
I I I I (D 0 0
SOURCE DESTINATION
0 R/M 0 SPECIFIER REGISTER
6 5 4 3 2 I 0
t
EFFECTIVE L
ADDRESS
MODE
[
REGISTER
h
0 0 0
,I~i
Instruction Fields:
Coprocessor ID Field -- Specifies which coprocessor in the system is to execute this
instruction. Freescale assemblers default to ID = 1 for the FPCP.
Effective Address Field -- Determines the addressing mode for external operands.
If R/M=0, this field is unused, and should be all zeros.
If R/M = 1, this field is encoded with an M68000 addressing mode as shown:
Addressing Mode Mode Register
Dn* O00 reg. number:Dn
An -- --
(An) 010
reg. number:An
(An)+ 011
reg. number:An
-(An) 100
reg. number:An
(d16,An) 101
reg. number:An
{d8,An,Xn) 110
reg. number:An
(bd,An,Xn) 110
reg. number:An
([bd,An,Xn],od) 110
reg. number:An
([bd,An],Xn,od) 110
reg. number:An
*Only if <fret> is Byte, Word, Long or Single.
Addressing Mode
(xxx).W
(xxx).L
#<data>
('d16,PC)
Mode
111
111
111
111
111
Register
i
I
ODO
O01
100
t
010
t 011
(d8,PC,Xn)
(bd,PC,Xn} 111 ! 011
([bd,PC.Xn],od) 111 i 011
([bd,PC].Xn.od) 111 i 011
R/M Field -- Specifies the source operand address mode.
0 -- The operation is register to register.
1 --The operation is <ea> to register.
Source Specifier Field -- Specifies the source register or data format.
If R/M =0, specifies the source floating-point data register, FPm.
If R/M = 1, specifies the source data format:
000 L Long Word Integer
001 S Single Precision Real
010 X Extended Precision Real
011 P Packed Decimal
Real
100 W Word Integer
101 D Double Precision Real
110 B Byte Integer
Destination Register Field -- Specifies the destination floating-point data register, FPn.
If R/M =0 and the source and destination fields are equal, the input operand is taken
from the specified floating-point data register, and the result is written into the sBme
register. If the single register syntax is used, Freescale assemblers set the source
and destination fields to the same value.
FREESCALE
4-110
MC68881/MC68882 USER'S MANUAL
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