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4.5. Buttons
The LinkIt 2523 HDK has four buttons that could support keypad functionality. To improve the LinkIt 2523 pin usage,
the buttons could be designed with double key feature, as shown in Table 9.
The JTAG debug feature is assigned to the same set of pins as the buttons on the HDK. The pins are SW6502, SW6503,
SW6504 and SW6505 and they will be disabled when JTAG feature is enabled using resistors R9001 and R9007. Buttons
are active if the resistors R9001 and R9007 are mounted to GND and GPIO18, GPIO20 and GPIO22 are set to keypad
when the LinkIt 2523 HDK is powered on. The locations are shown in Figure 10.
4.6. GPIO
LinkIt 2523 GPIOs provide the following internal states: digital high and digital low, input and output. The pins can be
configured using Easy PinMux Tool located under /doc folder. To learn more about the software registers and GPIO
functionality, please refer to the LinkIt 2523 API reference manual.
MT2523 digital die eFuse, MT2523 real time clock (RTC) source selection and pins assigned for user applications are
GPIO features that could be customized for user defined applications.
This document contains information that is proprietary to MediaTek Inc. ("MediaTek") and/or its licensor(s).
Any unauthorized use, reproduction or disclosure of this document in whole or in part is strictly prohibited.
LinkIt 2523 HDK User's Manual
Figure 9. The positions of LED indicators and debugging footprint
Table 9. Buttons and corresponding keypad functionality
© 2015 - 2016 MediaTek Inc.
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