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Rev. 1.10
20
March 02, 2020
Rev. 1.10
21
March 02, 2020
BS83A02L/BS83B04L
Ultra-Low Power Touch Key Flash MCU
BS83A02L/BS83B04L
Ultra-Low Power Touch Key Flash MCU
Initialisation Vector
16 bits
Look-up Table
BS83B04L
Initialisation Vector
Interrupt Vectors
Look-up Table
BS83A02L
000H
004H
n00H
nFFH
3FFH
7FFH
014H
14 bits
018H
Interrupt Vectors
Program Memory Structure
Special Vectors
Within the Program Memory, certain locations are reserved for the reset and interrupts. The location
0000H is reserved for use by the device reset for program initialisation. After a device reset is
initiated, the program will jump to this location and begin execution.
Look-up Table
Any location within the Program Memory can be defined as a look-up table where programmers
can store fixed data. To use the look-up table, the table pointer must first be setup by placing the
address of the look up data to be retrieved in the table pointer register, TBLP and TBHP. These
registers define the total address of the look-up table. The TBHP table pointer register is used for the
BS83B04L only.
After setting up the table pointer, the table data can be retrieved from the Program Memory using
the “TABRD[m]” or “TABRDL[m]” instructions, respectively. When the instruction is executed,
the lower order table byte from the Program Memory will be transferred to the user defined
Data Memory register [m] as specified in the instruction. The higher order table data byte from
the Program Memory will be transferred to the TBLH special register. Any unused bits in this
transferred higher order byte will be read as “0”.
The accompanying diagram illustrates the addressing data flow of the look-up table.
TBLP Register
Program Memory
Register TBLH
User Selected
Register
Addr
ess
Data
N bits
High Byte
Low Byte
Note: N=14 for BS83A02L
while N=16 for BS83B04L.
Last Page or Program Counter
High Byte for BS83A02L while
Last Page or TBHP Register
for BS83B04L
Table Program Example
The following example shows how the table pointer and table data is defined and retrieved from the
microcontroller. This example uses raw table data located in the Program Memory which is stored