@bperrybap I just tried all the "Hello World examples for these: hd44780_HC1627_I2C hd44780_I2Cexp hd44780_I2Clcd hd44780_NTCU165ECPB hd44780_NTCU20025ECPB hd44780_NTCUUserial hd44780_pinIO hd44780_I2Cexp flashed "Hello World" across the screen and then the LED started flashing. It is like …

HD44780 not working on my I2C LCD

outbackhut June 24, 2022, 1:03am 2

I2CexpDiag uploaded, then serial monitor says:

Display:

HD44780 initialization failed LCD 1602 I2C

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