MC68HC908QY2 MOTOROLA [Motorola, Inc], MC68HC908QY2 Datasheet - Page 65

• Manufacturer Part Number: MC68HC908QY2
• Description: Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

6.5 Arithmetic/Logic Unit (ALU)
6.6 Low-Power Modes
MOTOROLA
MC68HC908QY4•MC68HC908QT4•MC68HC908QY2•MC68HC908QT2•MC68HC908QY1•MC68HC908QT1
N — Negative flag
Z — Zero flag
C — Carry/Borrow Flag
The ALU performs the arithmetic and logic operations defined by the
instruction set.
Refer to the CPU08 Reference Manual (Motorola document order
number CPU08RM/AD) for a description of the instructions and
addressing modes and more detail about the architecture of the CPU.
The WAIT and STOP instructions put the MCU in low power-consumption
standby modes.
The CPU sets the negative flag when an arithmetic operation, logic
operation, or data manipulation produces a negative result, setting
bit 7 of the result.
The CPU sets the zero flag when an arithmetic operation, logic
operation, or data manipulation produces a result of $00.
The CPU sets the carry/borrow flag when an addition operation
produces a carry out of bit 7 of the accumulator or when a subtraction
operation requires a borrow. Some instructions — such as bit test and
branch, shift, and rotate — also clear or set the carry/borrow flag.
1 = Negative result
0 = Non-negative result
1 = Zero result
0 = Non-zero result
1 = Carry out of bit 7
0 = No carry out of bit 7
Central Processor Unit (CPU)
Central Processor Unit (CPU)
Arithmetic/Logic Unit (ALU)
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