MC908AB32CFUE Datasheet, PDF (344/392 Pages) Freescale Semiconductor, Inc – Microcontrollers

External Interrupt (IRQ)
18.6 IRQ Module During Break Interrupts
The system integration module (SIM) controls whether the IRQ latch can
be cleared during the break state. The BCFE bit in the break flag control
register (BFCR) enables software to clear the latches during the break
state. (See Section 8. System Integration Module (SIM).)
To allow software to clear the IRQ latch during a break interrupt, write a
logic 1 to the BCFE bit. If a latch is cleared during the break state, it
remains cleared when the MCU exits the break state.
To protect the latches during the break state, write a logic 0 to the BCFE
bit. With BCFE at logic 0 (its default state), writing to the ACK bit in the
IRQ status and control register during the break state has no effect on
the IRQ latch.
Technical Data
344
External Interrupt (IRQ)
MC68HC908AB32 — Rev. 1.1
Freescale Semiconductor