All,
Just got a number of I2C LCD Backpack's and found out they are looking for 16-pin LCDs....my are all 14-pin <Sarcasm>Conveniently, the backpack has no numbers on the interface pins</Sarcasm>, so you can tell which solder pad is for pin 1, and which one is for pin 14...so I can't even be sure I'm using the right pins. These LCDs work just fine with my Arduinos, so I'm thinking they should be able to work with the backpack...if I only knew what pins to use. Anyone know??
Thank you very much for your assistance
John
Using 14-pin LCD with 16-pin LCD Backpack??
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- john3exonets
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- adafruit_support_bill
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Re: Using 14-pin LCD with 16-pin LCD Backpack??
The backpack is designed for standard HD44780 character LCDs. Aside from the 18-pin RGB variants, character LCDs are pretty universally 16 pin devices. Where did you find the 14-pin displays? If they do not use a HD44780 controller, they may not be compatible with the backpack library.
This data sheet shows the standard 16-bit pinout. The tutorial shows how the backpack attaches to a display.
This data sheet shows the standard 16-bit pinout. The tutorial shows how the backpack attaches to a display.
- john3exonets
- Posts: 17
- Joined: Sun Oct 21, 2012 7:33 pm
Re: Using 14-pin LCD with 16-pin LCD Backpack??
They are Optrex DMC16230 16 x 2 LCDs. They are HD44780 driven, or at least they respond correctly to the signals and work with the Arduino LCD library...I'm using several right now in some projects using a 4-pin bus. Here's a datasheet I found on the Internet (http://www.digchip.com/datasheets/parts ... 30-pdf.php) They are only 14-pin.
Thanks for your help!
John
Thanks for your help!
John
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Re: Using 14-pin LCD with 16-pin LCD Backpack??
14 pin displays often just dont have a backlight - they'll work fine
- adafruit_support_rick
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Re: Using 14-pin LCD with 16-pin LCD Backpack??
The extra two pins are for the backlight. Your LCDs don't have backlights. Here's a picture of the backpack board layout, with pins 15 and 16 located. Just leave those empty and attach your LCD to pins 1-14.
- john3exonets
- Posts: 17
- Joined: Sun Oct 21, 2012 7:33 pm
Re: Using 14-pin LCD with 16-pin LCD Backpack??
Yep, that worked! Down to two pins to my Arduino now Thanks!
Please be positive and constructive with your questions and comments.