
PIC18F2480/2580/4480/4580
DS39637A-page 362
Preliminary
2004 Microchip Technology Inc.
TABLE 25-1:
OPCODE FIELD DESCRIPTIONS
Field
Description
a
RAM access bit
a =
0
: RAM location in Access RAM (BSR register is ignored)
a =
1
: RAM bank is specified by BSR register
Bit address within an 8-bit file register (0 to 7).
Bank Select Register. Used to select the current RAM bank.
ALU status bits:
C
arry,
D
igit
C
arry,
Z
ero,
Ov
erflow,
N
egative.
Destination select bit
d =
0
: store result in WREG
d =
1
: store result in file register f
Destination: either the WREG register or the specified register file location.
8-bit Register file address (00h to FFh), or 2-bit FSR designator (0h to 3h).
12-bit Register file address (000h to FFFh). This is the source address.
12-bit Register file address (000h to FFFh). This is the destination address.
Global Interrupt Enable bit.
Literal field, constant data or label (may be either an 8-bit, 12-bit or a 20-bit value)
Label name
The mode of the TBLPTR register for the table read and table write instructions.
Only used with table read and table write instructions:
No change to register (such as TBLPTR with table reads and writes)
Post-Increment register (such as TBLPTR with table reads and writes)
Post-Decrement register (such as TBLPTR with table reads and writes)
Pre-Increment register (such as TBLPTR with table reads and writes)
The relative address (2’s complement number) for relative branch instructions or the direct address for
Call/Branch and Return instructions
Program Counter.
Program Counter Low Byte.
Program Counter High Byte.
Program Counter High Byte Latch.
Program Counter Upper Byte Latch.
Power-down bit.
Product of Multiply High Byte.
Product of Multiply Low Byte.
Fast Call/Return mode select bit
s =
0
: do not update into/from shadow registers
s =
1
: certain registers loaded into/from shadow registers (Fast mode)
21-bit Table Pointer (points to a Program Memory location).
8-bit Table Latch.
Time-out bit.
Top-of-Stack.
Unused or unchanged.
Watchdog Timer.
Working register (accumulator).
Don’t care (‘
0
’ or ‘
1
’). The assembler will generate code with x =
0
. It is the recommended form of use for
compatibility with all Microchip software tools.
7-bit offset value for indirect addressing of register files (source).
7-bit offset value for indirect addressing of register files (destination).
Optional argument.
Indicates an indexed address.
The contents of
text
.
Specifies bit
n
of the register indicated by the pointer
expr
.
Assigned to.
Register bit field.
In the set of.
User defined term (font is Courier).
bbb
BSR
C, DC, Z, OV, N
d
dest
f
f
s
f
d
GIE
k
label
mm
*
*+
*-
+*
n
PC
PCL
PCH
PCLATH
PCLATU
PD
PRODH
PRODL
s
TBLPTR
TABLAT
TO
TOS
u
WDT
WREG
x
z
s
z
d
{ }
[text]
(text)
[expr]<n>
→
< >
∈
italics