Tutorial How to Expand IO in QMK firmware with Pro Micro Using I2C GPIO Expander

Опубликовано: 13 Январь 2022
на канале: FREE WING

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[No Speech, No BGM] QMK Tutorial QMK firmware Expand I/O for many scanlines matrix keyboard with Pro Micro
How to use IO Expander I2C GPIO Expander
Quantum Mechanical Keyboard Firmware

Problem: ProMicro not Enough GPIO pin to Handle Keyboard Matrix .
Solution: Using I2C GPIO Expander .

Feature
Consume I2C's 2 pins, Becomes 16 pins !! (two PCF8574)
Using eight PCF8574 to Can Handle 8 x 8 scanlines = Max 256 keys . By 2 GPIO pins .
(Using eight PCF8575 to Maximum 16 bit x 8 module = 128 pins = 64 x 64 = 4096 keys Ha Ha Ha !)

Use I2C GPIO Expander
PCF8574 8-bit I2C/SMBus I/O expander
How to Coding Own matrix.c

FREE WING's Homepage
http://www.neko.ne.jp/~freewing/hardw...

This Expand I/O QMK firmware Source code and Hand Wired Schematics
It is Contain Anti Ghosting and 6KRO limit .
https://github.com/FREEWING-JP/qmk_fi...

Multiplexer / Demultiplexer / Decoder version
• Tutorial How to Expand IO in QMK firm...
https://github.com/FREEWING-JP/qmk_fi...

QMK firmwareで I/Oピンが足りない場合に I2Cの GPIOエキスパンダを使用して IOを拡張する解決方法 (QMK firmware expand I/O for many matrix keyboard、How to use I2C GPIO Expander PCF8574 and PCF8575)