LCD Library (Initialization Issue)

Quick question for the regulars here.

I have the all to common issue of the row of squares in my lcd's top row and a blank bottom row (it's a standard hd44780 compatible lcd). It's actually a 16x1 (which is wired as an 8x2 internally!!), but i've allowed for this in my code. My sketch works fine on a breadboard with the arduino hooked up, but when I transfer the lcd to my circuit board, I get the row of squares.

I'm pretty certain this is down to my not very good soldering, and although I can't see an issue, i'll reflow all the joints when I get a chance. My question is: Does the arduino LCD library still have initalization issues? I just want to make sure I haven't got two seperate issues (poor soldering AND dodgy LCD initialization)

Thanks

I'm pretty certain this is down to my not very good soldering, and although I can't see an issue, i'll reflow all the joints when I get a chance. My question is: Does the arduino LCD library still have initalization issues? I just want to make sure I haven't got two seperate issues (poor soldering AND dodgy LCD initialization)

The library works well almost all of the time. There appear to be some issues with some displays when run in the four-bit mode, probably due to those displays being out of spec. People having problems with those displays can usually get them to work with the LiquidCrystal440 library or it's updated version. To get a copy start here:--> Google Code Archive - Long-term storage for Google Code Project Hosting. and follow the Downloads link to get to the latest version.

In your case, since it worked on the breadboard, I would suspect your soldering. Why don't you post a photo and let us take a look.

I hope you didn't forget to connect LCD pin 5 to GND.

Don

Yep, pin 5 is tied to GND alright. The soldering and circuitry's a bit of a mess. I might put it up, but it might end up causing confusion instead of helping matters.

Funny you mention 4-bit mode, as that is what i'm using, but as we've agreed, if it worked on the breadboard, it should work on the trackboard.

I'll reflow the connections later, and test it again in the morning. If it's still not working, i'll report back with photos ready to go. If it is working, i'll report back the good news.

Should reflowing PIN 5 and 6, along with my data pin connections (11 - 14), be sufficent to resolve this if is in indeed a soldering issue? I'll probably reflow all the LCD pins anyway, but just interested to know, as i'm guessing it's a data transmission/initialization issue.

Thanks,
Garry

Just to report back that I found my problem. I had my 'D7' pin on the LCD running to GND. Always the simplest mistakes that can stump you :slight_smile:

All the same, thanks to floresta for your help, which re-affirmed my thinking that the problem was of my own making, and not the LCD library.