MC68HC908JL3E Datasheet, PDF (177/226 Pages) Motorola, Inc – Microcontrollers

Keyboard Interrupt Module (KBI)
Low-Power Modes
14.5 Low-Power Modes
The WAIT and STOP instructions put the MCU in low power-
consumption standby modes.
14.5.1 Wait Mode
The keyboard modules remain 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.
14.5.2 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.
14.6 Keyboard Module During Break Interrupts
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.
MC68H(R)C908JL3E/JK3E/JK1E — Rev. 2.0
MOTOROLA
Keyboard Interrupt Module (KBI)
Technical Data
177