BC68F2420BC68F2420 Datasheet, PDF (24/116 Pages) Holtek Semiconductor Inc – 315/433MHz RF Super-regenerative Receiver SoC Flash MCU

BC68F2420
315/433MHz RF Super-regenerative
Receiver SoC Flash MCU
Data Memory
The Data Memory is a volatile area of 8-bit wide RAM internal memory and is the location where
temporary information is stored.
Structure
Divided into two areas, the first of these is an area of RAM, known as the Special Function Data
Memory. Here are located registers which are necessary for correct operation of the device. Many
of these registers can be read from and written to directly under program control, however, some
remain protected from user manipulation. The second area of Data Memory is known as the General
Purpose Data Memory, which is reserved for general purpose use. All locations within this area are
read and write accessible under program control.
The overall Data Memory is subdivided into two banks. The Special Purpose Data Memory registers
are accessible in Bank 0, along with the EEC register at address 40H, which is only accessible in
Bank 1. Switching between the different Data Memory banks is achieved by setting the Bank Pointer
to the correct value. The start address of the Data Memory for the device is the address 00H.
Special Purpose Data Memory
Bank: Address
0: 00H~3FH
1: 40H
General Purpose Data Memory
Capacity
Bank: Address
64×8
0: 40H~7FH
00H
Special Purpose
Data Memory
(Bank 0 ~ Bank 1)
3FH
40H
General Purpose
Data Memory
(Bank 0)
EEC at 40H in Bank 1
7FH
Bank 0
Data Memory Structure
General Purpose Data Memory
There are 64 bytes of general purpose data memory which are arranged in 40H~7FH of Bank 0. 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
24
May 24, 2017