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HT66FM5440
Brushless DC Motor A/D Flash MCU
HT66FM5440
Brushless DC Motor A/D Flash MCU
If the stack is overflow, the first Program Counter save in the stack will be lost.
Stack
Pointer
Stack Level �
Stack Level 1
Stack Level 3
:
:
:
Stack Level �
Program Memory
Program Co�nter
Bottom of Stack
Top of Stack
Arithmetic and Logic Unit – ALU
The arithmetic-logic unit or ALU is a critical area of the microcontroller that carries out arithmetic
and logic operations of the instruction set. Connected to the main microcontroller data bus, the ALU
receives related instruction 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 operations may
result in carry, borrow or other status changes, the status register will be correspondingly updated to
reflect these changes. The ALU supports the following functions:
• Arithmetic operations:
ADD, ADDM, ADC, ADCM, SUB, SUBM, SBC, SBCM, DAA,
LADD, LADDM, LADC, LADCM, LSUB, LSUBM, LSBC, LSBCM, LDAA
• Logic operations:
AND, OR, XOR, ANDM, ORM, XORM, CPL, CPLA,
LAND, LANDM, LOR, LORM, LXOR, LXORM, LCPL, LCPLA
• Rotation:
RRA, RR, RRCA, RRC, RLA, RL, RLCA, RLC,
LRR, LRRA, LRRCA, LRRC, LRLA, LRL, LRLCA, LRLC
• Increment and Decrement:
INCA, INC, DECA, DEC,
LINCA, LINC, LDECA, LDEC
• Branch decision:
JMP, SZ, SZA, SNZ, SIZ, SDZ, SIZA, SDZA, CALL, RET, RETI,
LSNZ, LSZ, LSZA, LSIZ, LSIZA, LSDZ, LSDZA