Register Addressing
6-3
Addressing Modes
6.2
Register Addressing
In register addressing, a CPU register contains the operand, as shown in this
example:
ABSF R1 ; R1 = |R1|
The syntax for the CPU registers, the assembler syntax, and the assigned
function for those registers are listed in Table 6–1.
Table 6–1. CPU Register Address/Assembler Syntax and Function
Register Name
Machine Address
Assigned Function
R0
R1
R2
R3
R4
R5
R6
R7
AR0
AR1
AR2
AR3
AR4
AR5
AR6
AR7
DP
IR0
IR1
BK
SP
ST
IE
IF
IOF
RS
RE
RC
00h
01h
02h
03h
04h
05h
06h
07h
08h
09h
0Ah
0Bh
0Ch
0Dh
0Eh
0FH
10h
11h
12h
13h
14h
15h
16h
17h
18h
19h
1Ah
1Bh
Extended-precision register 0
Extended-precision register 1
Extended-precision register 2
Extended-precision register 3
Extended-precision register 4
Extended-precision register 5
Extended-precision register 6
Extended-precision register 7
Auxiliary register 0
Auxiliary register 1
Auxiliary register 2
Auxiliary register 3
Auxiliary register 4
Auxiliary register 5
Auxiliary register 6
Auxiliary register 7
Data-page pointer
Index register 0
Index register 1
Block-size register
Active stack pointer
Status register
CPU/DMA interrupt-enable
CPU interrupt flags
I/O flags
Repeat start address
Repeat end address
Repeat counter