Datasheet

Keyboard Interrupt Module (KBI)
Technical Data MC68HC908LJ12 — Rev. 2.1
364 Keyboard Interrupt Module (KBI) Freescale Semiconductor
19.3 Features
Features of the keyboard interrupt module include the following:
• Eight keyboard interrupt pins with pullup devices
• Separate keyboard interrupt enable bits and one keyboard
interrupt mask
• Programmable edge-only or edge- and level- interrupt sensitivity
• Exit from low-lower modes
19.4 I/O Pins
The eight keyboard interrupt pins are shared with standard port I/O pins.
The full name of the KBI pins are listed in Table 19-1. The generic pin
name appear in the text that follows.
Addr.Register Name Bit 7654321Bit 0
$001B
Keyboard Status and
Control Register
(KBSCR)
Read:0000KEYF 0
IMASKK MODEK
Write:
ACKK
Reset:00000000
$001C
Keyboard Interrupt
Enable Register
(KBIER)
Read:
KBIE7 KBIE6 KBIE5 KBIE4 KBIE3 KBIE2 KBIE1 KBIE0
Write:
Reset:00000000
= Unimplemented
Figure 19-1. KBI I/O Register Summary
Table 19-1. Pin Name Conventions
KBI
Generic Pin Name
Full MCU Pin Name
Pin Selected for KBI Function by
KBIEx Bit in KBIER
KBI0–KBI3 PTA0/KBI0–PTA3/KBI3 KBIE0–KBIE3
KBI4–KBI7 PTD4/KBI4–PTD7/KBI7 KBIE4–KBIE7