mc68hc908rc24d Freescale Semiconductor, Inc, mc68hc908rc24d Datasheet - Page 57

• Manufacturer Part Number: mc68hc908rc24d
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

5.5 Arithmetic/Logic Unit (ALU)
5.6 Low-Power Modes
MC68HC908RC24 — Rev. 1.1
Freescale Semiconductor
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, Freescale 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 produce 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)
Advance Information
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