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[on:]

Sorry I know that's a bit of a vague question

I've had a 16x2 Serial LCD running absolutely fine for over a year and then the other day I turn it on and....nothing.
When powered on, the screen lights up for a second and displays random characters. Then the backlight goes off and the display goes blank. Nothing I've tried has coaxed it into doing anything at all.

• I've checked the screen is getting the right voltage - it seems to be
• I've checked the arduino is outputting through the tx pin - it seems to be, and I can see it outputting through the serial monitor
• I've tried sending all manner of reset commands to the screen with no effect - in fact it doesn't seem to matter whether its rx line is connected or not, it doesn't respond in any way

I know it really should have been connected via Software Serial but I'd always gotten away with it connected straight to the tx pin (so far). Is it possible the screen's been sent some bad instructions when powering up the board? Looking at the spec sheet I get the feeling there isn't, but is there a hard reset that can be performed somehow?

Thanks for any advice you can offer.

[Reply #1 on:]

Without a datasheet for you specific LCD its impossible to imagine what could be wrong. However, I've had a problem with a 16x2 display before where one of the data lines was shorted to ground, causing that bit to always be low. It still managed to initialize but all the characters were jumbled. Might be helpful to check the traces.

[Reply #2 on:]

Thanks for the advice, I'll double check on that.

[Reply #3 on:]

When powered on, the screen lights up for a second and displays random characters. Then the backlight goes off and the display goes blank.

Have you checked your power supply?

Don

[Reply #4 on:]

Yes, checked that with a multimeter, looks ok. It's as if the screen boots up, hits some bad instructions and then shuts down. I've checked for shorts too and can't find anything obvious, so I'm out of ideas on this one.