ht82m75r Holtek Semiconductor Inc., ht82m75r Datasheet - Page 9

• Manufacturer Part Number: ht82m75r
• Description: I/o Type 8-bit Otp Mcu
• Manufacturer: Holtek Semiconductor Inc.

Arithmetic and Logic Unit - ALU
The arithmetic-logic unit or ALU is a critical area of the
microcontroller that carries out arithmetic and logic op-
erations of the instruction set. Connected to the main
microcontroller data bus, the ALU receives related in-
struction codes and performs the required arithmetic or
logical operations after which the result will be placed in
the specified register. As these ALU calculation or oper-
ations may result in carry, borrow or other status
changes, the status register will be correspondingly up-
dated to reflect these changes. The ALU supports the
following functions:
Program Memory
The Program Memory is the location where the user
code or program is stored. The device is supplied with
One-Time Programmable, OTP, memory where users
can program their application code into the device. By
using the appropriate programming tools, OTP devices
Note:
Rev. 1.10
TABRDC[m]
TABRDL[m]
Instruction
Arithmetic operations: ADD, ADDM, ADC, ADCM,
SUB, SUBM, SBC, SBCM, DAA
Logic operations: AND, OR, XOR, ANDM, ORM,
XORM, CPL, CPLA
Rotation RRA, RR, RRCA, RRC, RLA, RL, RLCA,
RLC
Increment and Decrement INCA, INC, DECA, DEC
Branch decision, JMP, SZ, SZA, SNZ, SIZ, SDZ,
SIZA, SDZA, CALL, RET, RETI
PC11~PC8: Current program counter bits when TBHP is disabled
TBHP register bit3~bit0 when TBHP is enabled
@7~@0: Table Pointer TBLP bits
Program Memory Structure
PC11
b11
1
PC10
b10
1
PC9
b9
1
PC8
b8
1
Table Location
@7
@7
b7
Table Location Bits
9
@6
@6
b6
offer users the flexibility to freely develop their applica-
tions which may be useful during debug or for products
requiring frequent upgrades or program changes. OTP
devices are also applicable for use in applications that
require low or medium volume production runs.
Structure
The Program Memory has a capacity of 4K 15 bits. The
Program Memory is addressed by the Program Counter
and also contains data, table information and interrupt
entries. Table data, which can be setup in any location
within the Program Memory, is addressed by separate
table pointer registers.
Special Vectors
Within the Program Memory, certain locations are re-
served for special usage such as reset and interrupts.
Location 000H
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 execu-
tion.
Location 004H
This vector is used by serial interface. When 8-bits of
data have been received or transmitted success-fully
from serial interface. The program will jump to this lo-
cation and begin execution if the interrupt is enable
and the stack is not full.
Location 008H
This vector is used by the timer/event counter. If a
counter overflow occurs, the program will jump to this
location and begin execution if the timer interrupt is
enabled and the stack is not full.
Location 00CH
This vector is used by the external interrupt. If the INT
external input pin on the device receives a high to low
transition, the program will jump to this location and
begin execution, if the interrupt is enabled and the
stack is not full.
Table location
Any location in the program memory can be used as
look-up tables. There are three method to read the
ROM data by two table read instructions: TABRDC
and
lower-order byte to the specified data memory, and
the higher-order byte to TBLH (08H).
@5
@5
b5
TABRDL , transfer the contents of the
@4
@4
b4
HT82M75R/HT82M75RE
HT82K75R/HT82K75RE
@3
@3
b3
@2
@2
b2
@1
@1
b1
June 11, 2010
@0
@0
b0