Data Memory Addressing; General Purpose Data Memory; Special Purpose Data Memory - Holtek HT67F2350 Manual

Data Memory Addressing

For these devices that support the extended instructions, there is no Bank Pointer for Data Memory.
The Bank Pointer, PBP, is only available for Program Memory. For Data Memory the desired Sector
is pointed by the MP1H or MP2H register and the certain Data Memory address in the selected
sector is specified by the MP1L or MP2L register when using indirect addressing access.
Direct Addressing can be used in all sectors using the corresponding instruction which can address
all available data memory space. For the accessed data memory which is located in any data
memory sectors except sector 0, the extended instructions can be used to access the data memory
instead of using the indirect addressing access. The main difference between standard instructions
and extended instructions is that the data memory address "m" in the extended instructions can be
from 11 bits to 13 bits depending upon which device is selected, the high byte indicates a sector and
the low byte indicates a specific address.

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 RAM memory that is known as General Purpose
Data Memory. This area of Data Memory is fully accessible by the user programming for both
reading and writing operations. By using the bit operation 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 readable and writeable but some are
protected and are readable 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 "00H".
Rev. 1.60
Advanced A/D Flash MCU with LCD & EEPROM
00H
Special Purpose
Data Memory
(Sector 0 ~ Sector 1)
7FH
80H
General Purpose
Data Memory
(Sector 0 ~ Sector N)
FFH Sector 0
Sector 1
Note: N= 5 for HT67F2350;
N=11 for HT67F2360;
N=23 for HT67F2370;
N=31 for HT67F2390
Data Memory Structure
68
HT67F2350/HT67F2360
HT67F2370/HT67F2390
Sector 2 only for
HT67F2370/90
LCD Memory
in Sector 4
Sector N
May 16, 2019