"> <@9names:matrix.org> the hal..." <- i'm not sure i understand the question, but if you're asking how to use the hd44780-driver crate the best places to look are the docs: https://docs.rs/hd44780-driver/latest/hd44780_driver/struct.HD44780.html and the examples https://github.com/JohnDoneth/hd44780-driver/blob/master/examples/stm32f429disco-i2c/src/main.rs