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ST62T35B/E35B
MEMORY MAP
(Cont’d)
1.3.3 Data Space
Data Space accommodates all the data necessary
for processing the user program. This space com-
prises the RAM resource, the processor core and
peripheral registers, as well as read-only data
such as constants and look-up tables in Program
memory.
1.3.3.1 Data ROM
All read-only data is physically stored in program
memory, which also accommodates the Program
Space. The program memory consequently con-
tains the program code to be executed, as well as
the constants and look-up tables required by the
application.
The Data Space locations in which the different
constants and look-up tables are addressed by
the processor core may be thought of as a 64-byte
window through which it is possible to access the
read-only data stored in Program memory.
1.3.3.2 Data RAM/EEPROM
In ST6235B and ST62E35B devices, the data
space includes 60 bytes of RAM, the accumulator
(A), the indirect registers (X), (Y), the short direct
registers (V), (W), the I/O port registers, the pe-
ripheral data and control registers, the interrupt
option register and the Data ROM Window regis-
ter (DRW register).
Additional RAM and EEPROM pages can also be
addressed using banks of 64 bytes located be-
tween addresses 00ST62T35B and ST62E35Bh
and 3Fh.
1.3.4 Stack Space
Stack space consists of six 12-bit registers which
are used to stack subroutine and interrupt return
addresses, as well as the current program counter
contents.
Table 3. Additional RAM/EEPROM Banks.
Table 4. ST62T35B Data Memory Space
Device
RAM
EEPROM
2 x 64 bytes
ST62T35B
2 x 64 bytes
DATAand EEPROM
000h
03Fh
040h
07Fh
080h
081h
082h
083h
084h
0BFh
0C0h
0C1h
0C2h
0C3h
0C4h
0C5h
0C6h
0C7h
0C8h*
0C9h*
0CAh*
0CBh*
0CCh
0CDh
0CEh
0CFh
0D0h
0D1h
0D2h
0D3h
0D4h
0D5h
0D6h
0D7h
0D8h
0D9h
0DAh
0DBh
0DCh*
0DDh
0DEh
0DFh
0E0h
0E1h
0E2h
0E3h
0E8h
0E9h
0EAh
0EBh
0ECh
DATA ROM WINDOW AREA
X REGISTER
Y REGISTER
V REGISTER
W REGISTER
DATARAM
PORT A DATAREGISTER
PORT B DATAREGISTER
PORT C DATAREGISTER
PORT D DATAREGISTER
PORT A DIRECTION REGISTER
PORT B DIRECTION REGISTER
PORT C DIRECTION REGISTER
PORT D DIRECTION REGISTER
INTERRUPT OPTION REGISTER
DATA ROM WINDOW REGISTER
ROM BANK SELECT REGISTER
RAM/EEPROM BANK SELECT REGISTER
PORT A OPTION REGISTER
PORT B OPTION REGISTER
PORT C OPTION REGISTER
PORT D OPTION REGISTER
A/D DATAREGISTER
A/D CONTROL REGISTER
TIMER 1 PRESCALER REGISTER
TIMER 1 COUNTER REGISTER
TIMER 1 STATUS/CONTROLREGISTER
RESERVED
UARTDATA SHIFT REGISTER
UART STATUS CONTROL REGISTER
WATCHDOG REGISTER
RESERVED
I/O INTERRUPT POLARITY REGISTER
OSCILLATOR CONTROL REGISTER
SPI INTERRUPT DISABLE REGISTER
SPI DATAREGISTER
RESERVED
EEPROM CONTROL REGISTER
ARTIM16 COMPAREMASK REG. LOW BYTE MASK
ARTIM16 2ND STATUSCONTROL REGISTER SCR2
ARTIM16 3RD STATUSCONTROL REGISTER SCR3
ARTIM16 4TH STATUS CONTROLREGISTER SCR4
ARTIM16 1ST STATUSCONTROL REGISTER SCR1
ARTIM16 RELOAD CAPTURE REG. HIGH BYTE RLCP
ARTIM16 RELOAD CAPTURE REG. LOW BYTE RLCP
ARTIM16 CAPTUREREGISTER HIGH BYTE CP
ARTIM16 CAPTURE REGISTER LOW BYTE CP
ARTIM16COMPAREVALUEREGISTERHIGHBYTECMP 0EDh
ARTIM16COMPAREVALUEREGISTERLOWBYTECMP 0EEh
ARTIM 16 COMPARE MASK REG. HIGH BYTE MASK
RESERVED
0EFh
0F0h
0FBh
OFCh
0FDh
0FEh
OFFh
PORT E DATA REGISTER
PORT E DIRECTION REGISTER
PORT E OPTION REGISTER
ACCUMULATOR
* WRITE ONLYREGISTER
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