MC68HC08AZ16 Datasheet, PDF (318/527 Pages) Motorola, Inc – HCMOS Microcontroller Unit

Keyboard Module (KB)
Functional description
The keyboard flag bit (KEYF) in the keyboard status and control register
can be used to see if a pending interrupt exists. The KEYF bit is not
affected by the keyboard interrupt mask bit (IMASKK) which makes it
useful in applications where polling is preferred.
To determine the logic level on a keyboard interrupt pin, use the data
direction register to configure the pin as an input and read the data
register.
NOTE:
Setting a keyboard interrupt enable bit (KBxIE) forces the corresponding
keyboard interrupt pin to be an input, overriding the data direction
register. However, the data direction register bit must be a logic zero for
software to read the pin.
5-kbd
MOTOROLA
Keyboard Module (KB)
MC68HC08AZ32
317