BS2824 Holtek Semiconductor Inc., BS2824 Datasheet - Page 16

• Manufacturer Part Number: BS2824
• Description: Touch Key Mcu
• Manufacturer: Holtek Semiconductor Inc.

BS2824/BS2854/BS2868
Touch Key MCU
Note:
Rev. 1.00
TABRDC [m]
TABRDL [m]
Instruction
Special Vectors
Look-up Table
PC11~PC8: Current Program Counter bits
@7~@0: Table Pointer TBLP bits
For the BS2824, BS2854, the Table address location is 11 bits, i.e. from b10~b0.
For the BS2868, the Table address location is 12 bits, i.e. from b11~b0
Within the Program Memory, certain locations are reserved for special usage such as reset and
interrupts.
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 lower
order address of the look up data to be retrieved in the table pointer register, TBLP. This register
defines the lower 8-bit address of the look-up table.
After setting up the table pointer, the table data can be retrieved from the current Program Memory
page or last Program Memory page using the TABRDC[m] or TABRDL [m] instructions,
respectively. When these instructions are 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 .
This vector 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.
This vector is used by the external interrupt. If the external interrupt pin on the device receives an
edge transition, the program will jump to this location and begin execution if the external interrupt
is enabled and the stack is not full. The external interrupt active edge transition type, whether high
to low, low to high or both is specified in the CTRL1 register.
These internal vectors are used by the Timer/Event Counters. If a Timer/Event Counter overflow
occurs, the program will jump to its respective location and begin execution if the associated
Timer/Event Counter interrupt is enabled and the stack is not full.
This internal vector is used by the internal Time Base. If a Time Base overflow occurs, the
program will jump to this location and begin execution if the Time Base counter interrupt is
enabled and the stack is not full.
Reset Vector
External interrupt vector
Timer/Event 0/1 counter interrupt vectors
Time base interrupt vector
PC11
b11
1
PC10
b10
1
PC9
b9
1
PC8
b8
1
BS2824, BS2854
Table Location
@7
@7
BS2868
b7
Device
Table Location Bits
16
@6
@6
b6
@5
@5
b5
Capacity
2K 15
4K 15
@4
@4
b4
@3
@3
b3
@2
@2
b2
January 27, 2010
@1
@1
b1
@0
@0
b0