M68CBL05C datasheet(39/286 Pages) FREESCALE

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Computer Operating Properly Module (COP)

MC68HC908GR8 • MC68HC908GR4 Data Sheet, Rev. 7

Freescale Semiconductor

3.6 Computer Operating Properly Module (COP)

3.6.1 Wait Mode

The COP remains active in wait mode. To prevent a COP reset during wait mode, periodically clear the

COP counter in a CPU interrupt routine.

3.6.2 Stop Mode

Stop mode turns off the COPCLK input to the COP and clears the SIM counter. Service the COP

immediately before entering or after exiting stop mode to ensure a full COP timeout period after entering

or exiting stop mode.

The STOP bit in the configuration register (CONFIG) enables the STOP instruction. To prevent

inadvertently turning off the COP with a STOP instruction, disable the STOP instruction by clearing the

STOP bit.

3.7 External Interrupt Module (IRQ)

3.7.1 Wait Mode

The IRQ module remains active in wait mode. Clearing the IMASK bit in the IRQ status and control

3.7.2 Stop Mode

The IRQ module remains active in stop mode. Clearing the IMASK bit in the IRQ status and control

3.8 Keyboard Interrupt Module (KBI)

3.8.1 Wait Mode

The keyboard module remains active in wait mode. Clearing the IMASKK bit in the keyboard status and

control register enables keyboard interrupt requests to bring the MCU out of wait mode.

3.8.2 Stop Mode

The keyboard module remains active in stop mode. Clearing the IMASKK bit in the keyboard status and

control register enables keyboard interrupt requests to bring the MCU out of stop mode.

3.9 Low-Voltage Inhibit Module (LVI)

3.9.1 Wait Mode

If enabled, the LVI module remains active in wait mode. If enabled to generate resets, the LVI module can

generate a reset and bring the MCU out of wait mode.

M68CBL05C датащи(PDF) 39 Page - Freescale Semiconductor, Inc