Keypad Interface; Overview - Intel PXA27 Series Design Manual

Keypad Interface

This chapter describes the procedures for interfacing with the keypad controller of Intel
Processor Family (PXA27x processor).
18.1

Overview

The keypad interface block provides an interface to two styles of keypads: direct key and matrix
key, and supports both types of keypads simultaneously.
The direct keypad interface supports the direct keys and the rotary encoders used to implement
keys such as scroll keys and thumb wheels.
The matrix keypad interface supports manual and automatic scans of the keypad array. Additional
information concerning the different type of scan modes is documented in the keypad section of the
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Intel PXA27x Processor Family Developers Manual.
The direct keypad block supports eight input pins, whereas the matrix keypad block supports eight
output and eight input pins. Included within the keypad controller is debounce logic with a
programmable interval period. The internal debounce logic is disabled by setting the interval
period to zero.
All references to registers are documented in the Intel
Manual unless otherwise noted. The following information provides examples for specific
configurations. This section has not attempted to document all possible configuration, just those
configuration that are more commonly used.
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Intel PXA27x Processor Family Design Guide
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PXA27x Processor Family Developers
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PXA27x
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