SPRS079E – OCTOBER 1998 – REVISED AUGUST 2000
27
POST OFFICE BOX 1443
•
HOUSTON, TEXAS 77251–1443
memory-mapped registers
The ’5402 has 27 memory-mapped CPU registers, which are mapped in data memory space addresses 0h to
1Fh. Table 9 gives a list of CPU memory-mapped registers (MMRs) available on ’5402. The device also has
a set of memory-mapped registers associated with peripherals. Table 10, Table 11, and Table 12 show
additional peripheral MMRs associated with the ’5402.
Table 9. CPU Memory-Mapped Registers
NAME
ADDRESS
DESCRIPTION
NAME
DEC
HEX
DESCRIPTION
IMR
0
0
Interrupt mask register
IFR
1
1
Interrupt flag register
–
2–5
2–5
Reserved for testing
ST0
6
6
Status register 0
ST1
7
7
Status register 1
AL
8
8
Accumulator A low word (15–0)
AH
9
9
Accumulator A high word (31–16)
AG
10
A
Accumulator A guard bits (39–32)
BL
11
B
Accumulator B low word (15–0)
BH
12
C
Accumulator B high word (31–16)
BG
13
D
Accumulator B guard bits (39–32)
TREG
14
E
Temporary register
TRN
15
F
Transition register
AR0
16
10
Auxiliary register 0
AR1
17
11
Auxiliary register 1
AR2
18
12
Auxiliary register 2
AR3
19
13
Auxiliary register 3
AR4
20
14
Auxiliary register 4
AR5
21
15
Auxiliary register 5
AR6
22
16
Auxiliary register 6
AR7
23
17
Auxiliary register 7
SP
24
18
Stack pointer register
BK
25
19
Circular buffer size register
BRC
26
1A
Block repeat counter
RSA
27
1B
Block repeat start address
REA
28
1C
Block repeat end address
PMST
29
1D
Processor mode status (PMST) register
XPC
30
1E
Extended program page register
–
31
1F
Reserved