MC68HC908JW32_09 Datasheet, PDF (191/232 Pages) Freescale Semiconductor, Inc – M68HC08 Microcontrollers

Chapter 15
Keyboard Interrupt Module (KBI)
15.1 Introduction
The keyboard interrupt module (KBI) provides eight independently maskable external interrupts which are
accessible via PTA0–PTA7 pins.
15.2 Features
Features of the keyboard interrupt module include:
• Eight keyboard interrupt pins with separate keyboard interrupt enable bits and one keyboard
interrupt mask
• Hysteresis buffers
• Programmable edge-only or edge- and level-interrupt sensitivity
• Exit from low-power modes
Addr.
$0016
$0017
Register Name
Keyboard Status ^Read:
and Control Register Write:
(KBSCR) _Reset:
Keyboard Interrupt Enable ^Read:
Register Write:
(KBIER) _Reset:
Bit 7
0
0
KBIE7
0
6
5
0
0
0
0
KBIE6 KBIE5
0
0
= Unimplemented
4
0
0
KBIE4
0
3
KEYF
0
KBIE3
0
Figure 15-1. KBI I/O Register Summary
2
0
ACKK
0
KBIE2
0
1
Bit 0
IMASKK MODEK
0
0
KBIE1 KBIE0
0
0
15.3 Pin Name Conventions
The eight keyboard interrupt pins are shared with standard port I/O pins. The full name of the KBI pins
are listed in Table 15-1. The generic pin name appear in the text that follows.
Table 15-1. Pin Name Conventions
KBI
Generic Pin Name
KBA0–KBA7
Full MCU Pin Name
PTA0/KBA0–PTA7/KBA7
Pin Selected for KBI Function
by KBIEx Bit in KBIER
KBIE0–KBIE7
MC68HC908JW32 Data Sheet, Rev. 6
Freescale Semiconductor
191