MOTOROLA
6-110
INSTRUCTION GLOSSARY
CPU16
REFERENCE MANUAL
FMULS
Operation:
Signed Fractional Multiply
FMULS
(E)
(D)
E : D[31
:
1]
0
E : D[0]
Description:
Multiplies a 16-bit signed fractional multiplicand contained in accu-
mulator E by a 16-bit signed fractional multiplier contained in accu-
mulator D. The implied radix points are between bits 15 and 14 of
the accumulators. The product is left-shifted one place to align the
radix point between bits 31 and 30, then placed in bits 31 to 1 of
concatenated accumulators E and D. D0 is cleared. The CCR carry
bit can be used to round the high word of the product — execute
FMULS, then ADCE #0.
When both accumulators contain $8000 (–1), the product is
$80000000 (–1.0) and the CCR V bit is set.
Syntax:
Standard
Condition Code Register:
S:
Not affected.
Not affected.
Not affected.
Not affected.
Set if E15
=
1 as a result of operation; else cleared.
Set if (E : D)
=
$00000000 as a result of operation; else cleared.
Set when operation is (–1)
2
; else cleared.
Set if D15
=
1 as a result of operation; else cleared.
Not affected.
Not affected.
Not affected.
Instruction Format:
MV:
H:
EV:
N:
Z:
V:
C:
IP:
SM:
PK:
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
S
MV
H
EV
N
Z
V
C
IP
SM
PK
—
—
—
—
—
—
—
Addressing Mode
INH
Opcode
3727
Operand
—
Cycles
8
F
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
n
.