MC68HC908KX8 Datasheet, PDF (66/310 Pages) Motorola, Inc – Microcontrollers

Central Processor Unit (CPU)
5.5 Arithmetic/Logic Unit (ALU)
The arithmetic/logic unit (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.
5.6 Low-Power Modes
The WAIT and STOP instructions put the MCU in low power-consumption
standby modes.
5.6.1 Wait Mode
The WAIT instruction:
• Clears the interrupt mask (I bit) in the condition code register,
enabling interrupts. After exit from wait mode by interrupt, the I bit
remains clear. After exit by reset, the I bit is set.
• Disables the CPU clock
5.6.2 Stop Mode
The STOP instruction:
• Clears the interrupt mask (I bit) in the condition code register,
enabling external interrupts. After exit from stop mode by external
interrupt, the I bit remains clear. After exit by reset, the I bit is set.
• Disables the CPU clock
After exiting stop mode, the CPU clock begins running after the oscillator
stabilization delay.
Technical Data
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MC68HC908KX8 • MC68HC908KX2 • MC68HC08KX8 — Rev. 1.0
Central Processor Unit (CPU)
MOTOROLA