Datasheet

11.2 External Signals Description
The KBI input pins can be used to detect either falling edges, or both falling edge and
low-level interrupt requests. The KBI input pins can also be used to detect either rising
edges, or both rising edge and high-level interrupt requests.
The signal properties of KBI are shown in the following table:
Table 11-1. External signals description
Signal Function I/O
KBIxPn Keyboard interrupt pins I
11.3 Register Definition
The KBI includes three registers:
• An 8-bit pin status and control register, KBIxSC
• An 8-bit pin enable register, KBIxPE
• An 8-bit edge select register, KBIxES
See the direct-page register summary in the Memory chapter for the absolute address
assignments for all KBI registers. This section refers to registers and control bits only by
their names.
Some MCUs may have more than one KBI, so register names include placeholder
characters to identify which KBI is being referenced.
Memory Map and Registers
KBI memory map
Absolute
address
(hex)
Register name
Width
(in bits)
Access Reset value
Section/
page
3C KBI Status and Control Register (KBI0_SC) 8 R/W 00h 11.4.1/282
307C KBIx Pin Enable Register (KBI0_PE) 8 R/W 00h 11.4.2/282
307D KBIx Edge Select Register (KBI0_ES) 8 R/W 00h 11.4.3/283
3D KBI Status and Control Register (KBI1_SC) 8 R/W 00h 11.4.1/282
307D KBIx Pin Enable Register (KBI1_PE) 8 R/W 00h 11.4.2/282
307E KBIx Edge Select Register (KBI1_ES) 8 R/W 00h 11.4.3/283
11.4
Chapter 11 Keyboard Interrupts (KBI)
MC9S08PA60 Reference Manual, Rev. 1, 9/2012
Freescale Semiconductor, Inc. 281