extend some GPIO for 157

[Jzhua]

I am going to extend some GPIO for 157 for keyboard, I found on EV board is a MCU of STM32L157 to implement, do you have any firmware information about this MCU

Source code or I2C protocol, or have other similar chips

[PatrickF]

I guess you talk about the MCU used as IO expanders on STM32MP157C-EV1 motherboard (MB1262).

The content of this STM32L152 MCU is internal only (used for tests purpose in addition to GPIO expander), I recommend to use cheaper/simpler I2C GPIO expanders. Unfortunately, ST STMPE1600 and STMPE1801 are not recommended for new designs.

To chose right I2C expander, you must also check with the 3rd party the support of Linux (if you plan to control them by Linux).

[Jzhua]

Thank you for your reply

I thought it would be great if you could open source, I could do some simple logic with a cheap MCU like stm32F030 and do the keyboard and the slow gpio extension at the same time