Keyboard Module During Break Interrupts - Motorola MC68HC908AB32 Technical Data Manual

Keyboard Interrupt Module (KBI)

19.8 Keyboard Module During Break Interrupts

Technical Data
352
The system integration module (SIM) controls whether the keyboard
interrupt latch can be cleared during the break state. The BCFE bit in the
break flag control register (BFCR) enables software to clear status bits
during the break state.
To allow software to clear the keyboard interrupt 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 latch during the break state, write a logic 0 to the BCFE
bit. With BCFE at logic 0 (its default state), writing to the keyboard
acknowledge bit (ACKK) in the keyboard status and control register
during the break state has no effect.
Keyboard Interrupt Module (KBI)
MC68HC908AB32 Rev. 1.0
—
MOTOROLA