I recently purchased this RGB LCD Shield with a 16x2 negative display:
https://www.adafruit.com/products/714
I soldered it altogether as per the assembly instructions (photos attached) and I am using the sample program that comes in the "Adafruit-RGB-LCD-Shield-Library-master" (see https://codebender.cc/sketch:157836).
The problem I have is that the buttons change the colors per the example program, but there is no text displayed. No Hello World or the number of milliseconds since start up. Just a blank screen that I can change the color of using the buttons.
I had some issues trying to fit the LCD screen onto the shield with the stackable headers, so I had to have the LCD pin headers at a slight angle, but I think the connections are good. I resoldered all of the pin connections to the LCD screen, both on the board and on the LCD screen. I resoldered all of the pins of the MLP23 chip. I'm just a novice solderer, but I think the connections look good. I don't think there are any shorts at least. Still no luck. Same behavior before and after.
Any suggestions? Are there particular pins/connections I can look at that are related to the text display?
-Mark
Issue with RGB LCD Shield 16x2
Moderators: adafruit_support_bill, adafruit
Please be positive and constructive with your questions and comments.
- mwomack
- Posts: 24
- Joined: Sat Sep 26, 2015 3:12 pm
Issue with RGB LCD Shield 16x2
- Attachments
-
- IMG_20150926_161119_653.jpg (593.01 KiB) Viewed 293 times
-
- IMG_20150926_161108_735.jpg (402.86 KiB) Viewed 293 times
-
- IMG_20150926_161056_286.jpg (179.05 KiB) Viewed 293 times
- mwomack
- Posts: 24
- Joined: Sat Sep 26, 2015 3:12 pm
Re: Issue with RGB LCD Shield 16x2
I should also mention that I tried my shield with two different Uno boards, same results of no text displayed, just the background color.
-Mark
-Mark
- adafruit_support_mike
- Posts: 67446
- Joined: Thu Feb 11, 2010 2:51 pm
Re: Issue with RGB LCD Shield 16x2
Have you adjusted the contrast potentiometer? That needs to be cranked most of the way to one side before the LCD starts to show output.
- mwomack
- Posts: 24
- Joined: Sat Sep 26, 2015 3:12 pm
Re: Issue with RGB LCD Shield 16x2
Yes, that was it! I adjusted the potentiometer and the text appeared! Glad to see I could handle the basic soldering after all.
I missed the Adjust Contrast portion of the tutorial. Argh.
Thank you!
-Mark
I missed the Adjust Contrast portion of the tutorial. Argh.
Thank you!
-Mark
- adafruit_support_mike
- Posts: 67446
- Joined: Thu Feb 11, 2010 2:51 pm
Re: Issue with RGB LCD Shield 16x2
That catches everyone the first couple of times. ;-)
Glad to hear it's working for you. Happy hacking!
Glad to hear it's working for you. Happy hacking!
Please be positive and constructive with your questions and comments.