Data Memory Addressing; General Purpose Data Memory; Special Purpose Data Memory - Holtek BS86DH12C Manual

Data Memory Addressing

For this device that supports the extended instructions, there is no Bank Pointer for Data Memory
addressing. 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 extended 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 has 10 valid
bits for the device, 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 programing 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. 1.00
High Voltage Touch A/D Flash MCU with HVIO
00H
Special Purpose
Data Memory
(Sector 0 ~ Sector 1)
7FH
80H
General Purpose
Data Memory
(Sector 0 ~ Sector 3)
Sector 0
FFH
Data Memory Structure
32
BS86DH12C
Sector 1
Sector 3
October 26, 2018