PIC18F6525_13 Datasheet, PDF (302/400 Pages) Microchip Technology – 64/80-Pin High-Performance, 64-Kbyte Enhanced Flash Microcontrollers with A/D

PIC18F6525/6621/8525/8621
MULLW
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Q Cycle Activity:
Q1
Decode
Multiply Literal with W
[ label ] MULLW k
0  k  255
(W) x k  PRODH:PRODL
None
0000 1101 kkkk kkkk
An unsigned multiplication is carried
out between the contents of W and
the 8-bit literal ‘k’. The 16-bit result is
placed in PRODH:PRODL register
pair. PRODH contains the high byte.
W is unchanged.
None of the Status flags are affected.
Note that neither overflow nor carry
is possible in this operation. A zero
result is possible but not detected.
1
1
Q2
Read
literal ‘k’
Q3
Process
Data
Q4
Write
registers
PRODH:
PRODL
Example:
MULLW 0xC4
Before Instruction
W
=
PRODH
=
PRODL
=
After Instruction
W
=
PRODH
=
PRODL
=
0xE2
?
?
0xE2
0xAD
0x08
MULWF
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Q Cycle Activity:
Q1
Decode
Multiply W with f
[ label ] MULWF f [,a]
0  f  255
a  [0,1]
(W) x (f)  PRODH:PRODL
None
0000 001a ffff ffff
An unsigned multiplication is carried out
between the contents of W and the
register file location ‘f’. The 16-bit result
is stored in the PRODH:PRODL
register pair. PRODH contains the high
byte.
Both W and ‘f’ are unchanged.
None of the Status flags are affected.
Note that neither overflow nor carry is
possible in this operation. A zero result
is possible but not detected. If ‘a’ is ‘0’,
the Access Bank will be selected,
overriding the BSR value. If
‘a’ = 1, then the bank will be selected
as per the BSR value (default).
1
1
Q2
Read
register ‘f’
Q3
Process
Data
Q4
Write
registers
PRODH:
PRODL
Example:
MULWF REG, 1
Before Instruction
W
=
REG
=
PRODH
=
PRODL
=
After Instruction
W
=
REG
=
PRODH
=
PRODL
=
0xC4
0xB5
?
?
0xC4
0xB5
0x8A
0x94
DS39612C-page 302
 2003-2013 Microchip Technology Inc.