HT45R37_11 Datasheet, PDF (14/100 Pages) Holtek Semiconductor Inc – TinyPowerTM C/R-F Type 8-Bit OTP MCU

HT45R37
Data Memory
The Data Memory is a volatile area of 8-bit wide RAM
internal memory and is the location where temporary in-
formation is stored. Divided into two sections, the first of
these is an area of RAM where special function registers
are located. These registers have fixed locations and
are necessary for correct operation of the device. Many
of these registers can be read from and written to di-
rectly under program control, however, some remain
protected from user manipulation. The second area of
Data Memory is reserved for general purpose use. All
locations within this area are read and write accessible
under program control.
Structure
The Data Memory is subdivided into two sections, the
Special Purpose Data Memory and the General Pur-
pose Data Memory. The start address of the Data Mem-
ory is the address ²00H². The last Data Memory
address is ²FFH².
00H
S p e c ia l P u r p o s e
D a ta M e m o ry
5FH
60H
G e n e ra l P u rp o s e
D a ta M e m o ry
FFH
Data Memory Structure
Note:
Most of the Data Memory bits can be directly ma-
nipulated using the ²SET [m].i² and ²CLR [m].i²
with the exception of a few dedicated bits. The
Data Memory can also be accessed through the
memory pointer registers MP0 and MP1.
General Purpose Data Memory
All microcontroller programs require an area of
read/write memory where temporary data can be stored
and retrieved for use later. It is this area of Data Memory
that is known as General Purpose Data Memory. This
area of Data Memory is fully accessible by the user pro-
gram for both read and write operations. By using the
²SET [m].i² and ²CLR [m].i² instructions individual bits
can be set or reset under program control giving the
user a large range of flexibility for bit manipulation in the
Data Memory.
Special Purpose Data Memory
This area of Data Memory is where registers, necessary
for the correct operation of the microcontroller, are
stored. Most of the registers are both read and write type
but some are protected and are read only, the details of
which are located under the relevant Special Function
Register section. Note that for locations that are unused,
any read instruction to these addresses will return the
value ²00H².
00H
01H
02H
03H
04H
05H
06H
07H
08H
09H
0A H
0B H
0C H
0D H
0E H
0FH
10H
11H
12H
13H
14H
15H
16H
17H
18H
19H
1A H
1B H
1C H
1D H
1E H
1FH
20H
21H
22H
23H
24H
25H
26H
27H
28H
29H
2A H
2B H
2C H
2D H
2E H
2FH
30H
31H
32H
33H
34H
35H
36H
37H
38H
39H
3A H
3B H
3C H
3D H
3E H
3FH
40H ~5H F
IA R 0
M P0
IA R 1
M P1
ACC
PCL
TB LP
TB LH
R TC C
STATU S
IN T C 0
TM R 0
TM R 0C
PA
PAC
PB
PBC
PC
PCC
PD
PDC
P W M 0L
P W M 0H
P W M 1L
P W M 1H
IN T C 1
M F IC 0
M F IC 1
ASCR0
ASCR1
ASCR2
ADRL
ADRH
ADCR
ACSR
C LK M O D
PAW U
PAPU
PBPU
PCPU
PDPU
IN T E D G E
M IS C
TM R AH
TM R AL
RCOCCR
TM R BH
TM R BL
RCOCR
S IM C T L 0
S IM C T L 1
S IM D R
S IM A R /S IM C T L 2
TM R 1
TM R 1C
: U n u s e d re a d a s "0 0 "
: U n u s e d re a d a s u n k n o w n
Special Purpose Data Memory
Rev. 1.20
14
February 25, 2011