I have a QP5521 from Jaycar working with I2C to parallel unit working really well. I changed it for a CE09541 from Core Electronics, which is I2C on the LCD package I thought it would be just swap and sing, but I get nothing on the screen except the background of the first row, I have no idea why. As far as I can tell they are near identical units. Has anyone else had issues like this or overcome some maybe clock differences between two units like these?
It looks like the QP5521 from Jaycar uses a HD44780 LCD controller whereas the CE09541 Waveshare LCD uses an AiP31068 LCD controller. There’s a good chance the actually display itself is identical, but if the driver module is different it may be expecting a different I2C address or protocol to communicate with it.
The full specifications for the Waveshare LCD can be found on their product wiki below. It seems they have examples for RPi, Pico, Arduino, ESP32, and the Jetson Nano so hopefully one of those code demos could get you out of trouble.
What microcontroller were you using with your display?
Thanks Trent I did examine that possibility but came up blank, so thanks for verifying that. I am using a Pico, I will examine what they have on their site and see if I can alter my library to support both.