I have the 20x4 that I have hooked up to the pro micro using the qwiic connector. I had just set it up and was going through the examples and tried to get it to read the output from a tmp117 sensor also hooked up via qwiic. Then one of the times I tried uploading it just started showing hearts on all cursor spots on the display. I tried switching back to the hello world example and a few other examples and no matter what it just displays that. I have tried restarting everything and after the start that says sparkfun and the version I can’t get it to change. Any tips?
Ensure the baud rates being used match; also try performing a reset as mentioned in the code box in this section https://learn.sparkfun.com/tutorials/av … de—basic
Try using just the LCD (without the TMP sensor on the bus).
After it gets working (if!), then go back to trying to implement the TMP…you might need to cut the traces for the i2c pull ups mentioned here https://learn.sparkfun.com/tutorials/qw … e-overview if it continues to give issues)
I tried to do these things all with the display by itslef on the bus. When I try to do the reset it just gives me a blank display and never shows the reset of the prompts. I also have it hooked up to a different pro micro and no change. Every time it starts it shows the firmware version then the whole screen fills with hearts and won’t change when I upload anything. It shows version 1.4 bad 9600.