NXP Semiconductors MC9S08LG16, Reference Manual

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MC9S08LG32 MCU Series, Rev. 5
Freescale Semiconductor 128
Chapter 7
Keyboard Interrupt (S08KBIV2)
7.1 Introduction
The keyboard interrupt KBI module provides up to eight independently-enabled, external interrupt
sources.
7.1.1 Module Configuration
The KBI module pins, KBIn can be repositioned under software control using KBI0, KBI1, KBI2, KBI3,
KBI4, KBI5, KBI6, and KBI7 bits in PINPS1 register as shown in
Table 7-1 . KBI0, KBI1, KBI2, KBI3,
KBI4, KBI5, KBI6, and KBI7 bits in PINPS1 register selects which general-purpose I/O ports are
associated with KBI operation.
7.1.2 KBI Clock Gating
The bus clock to the KBI can be gated on and off using the KBI bit in SCGC2. This bit is clear after any
reset, which disables the bus clock to this module. To conserve power, this bit can be cleared to disable the
clock to this module when not in use. For more details, see
Section 5.7, “Peripheral Clock Gating .”
Table 7-1. KBI Position Options
KBIn in PINPS1 Port Pin for KBI7 Port Pin for KBI6 Port Pin for KBI5 Port Pin for KBI4
0 (default) PTA6 PTA5 PTA4 PTA3
1 PTH3 PTH2 PTH1 PTH0
KBIn in PINPS1 Port Pin for KBI3 Port Pin for KBI2 Port Pin for KBI1 Port Pin for KBI0
0 (default) PTF0 PTF5 PTF4 PTF3
1 PTH5 PTH4 PTH7 PTH6