XC908AS60ACFU Motorola Semiconductor Products, XC908AS60ACFU Datasheet - Page 135

• Manufacturer Part Number: XC908AS60ACFU
• Description: MC68HC908AZ60A, MC68HC908AS60A Hcmos Microcontroller Unit Technical Data
• Manufacturer: Motorola Semiconductor Products

8.5 Arithmetic/logic unit (ALU)
MC68HC908AZ60A — Rev 2.0
MOTOROLA
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 number
CPU08RM/AD) for a description of the instructions and addressing
modes and more detail about CPU architecture.
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)
Technical Data
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