Eeprom Data Memory; Eeprom Data Memo; Eeprom Registe�S - Holtek BS83B24C Manual

BS83B24C/BS83C40C
Touch Flash MCU

EEPROM Data Memory

Each device contains an area of internal EEPROM Data Memory. EEPROM is by its nature a non-
volatile form of re-programmable memory, with data retention even when its power supply is
removed. By incorporating this kind of data memory, a whole new host of application possibilities
are made available to the designer. The availability of EEPROM storage allows information such
as product identification numbers, calibration values, specific user data, system setup data or other
product information to be stored directly within the product microcontroller. The process of reading
and writing data to the EEPROM memory has been reduced to a very trivial affair.
EEPROM Data Memory Structure
The EEPROM Data Memory capacity is 128×8 bits. Unlike the Program Memory and RAM Data
Memory, the EEPROM Data Memory is not directly mapped into memory space and is therefore not
directly addressable in the same way as the other types of memory. Read and Write operations to the
EEPROM are carried out in single byte operations using an address and a data register in Sector 0
and a single control register in Sector 1.
EEPROM Registers
Three registers control the overall operation of the internal EEPROM Data Memory. These are the
address register, EEA, the data register, EED and a single control register, EEC. As both the EEA
and EED registers are located in Sector 0, they can be directly accessed in the same was as any
other Special Function Register. The EEC register however, being located in Sector 1, can be read
from or written to indirectly using the MP1L/MP1H or MP2L/MP2H Memory Pointer and Indirect
Addressing Register, IAR1/IAR2. Because the EEC control register is located at address 40H in
Sector 1, the MP1L or MP2L Memory Pointer must first be set to the value 40H and the MP1H or
MP2H Memory Pointer high byte set to the value, 01H, before any operations on the EEC register
are executed.
Register
Name
7
EEA —
EED EED�
EEC —
• EEA Register
Bit 7
Name —
R/W —
POR —
Bit 7 Unimplemented, read as "0"
EEA6~EEA0: Data EEPROM address bit 6 ~ bit 0
Bit 6~0
• EED Register
Bit 7
Name EED�
R/W R/W
POR 0
EED7~EED0: Data EEPROM data bit 7 ~ bit 0
Bit 7~0
Rev. 1.00
Bit
6 5 4
EEA6 EEA5 EEA4
EED6 EED5 EED4
— — —
EEPROM Register List
6 5 4
EEA6 EEA5 EEA4
R/W R/W R/W
0 0 0
6 5 4
EED6 EED5 EED4
R/W R/W R/W
0 0 0
39
3 2 1
EEA3 EEA� EEA1
EED3 EED� EED1
WREN WR RDEN
3 2 1
EEA3 EEA� EEA1
R/W R/W R/W
0 0 0
3 2 1
EED3 EED� EED1
R/W R/W R/W
0 0 0
�e���a�� 0�� �01�
0
EEA0
EED0
RD
0
EEA0
R/W
0
0
EED0
R/W
0