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I just got Arduino (Uno) and I want to use the LCD that came w/ it (I got the Ultimate Microcontroller Pack, by Makershed). How should I connect it to the Arduino? Should I solder wires to the connection points? Should I connect it to a breadboard (one for itself) and wire it from that? Thx
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go with the breadboard option!

http://www.ladyada.net/learn/lcd/charlcd.html and follow this tutorial, it covers a fair bit of info, and does everything step by step (on a breadboard)

enjoy!
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Thanks!  smiley
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costa mesa, CA, united states
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Quote
Should I solder wires to the connection points?
That is what I did when I got my first LCD.
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Later if you want to put your LCD elsewhere, you can use some male/female jumpers and the mounting holes on the LCD sold at pololu.com

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I'm having a problem with my LCD. I'm following this tutorial - http://www.ladyada.net/learn/lcd/charlcd.html - I have the same LCD, but I can't get past the first step. My arduino's (UNO) LCD doesn't turn on or show anything on it. No squares or backlight. Any help?

My board ATM -

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Hofstadter's Law: It always takes longer than you expect, even when you take into account Hofstadter's Law.
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Looks to me that your breadboard probably has a break in the +5v and ground lines, right where there is a break in the blue line next to the ground line. However, this may have saved you from burning out the backlight, since most LCD displays need a resistor in series with the backlight. If you don't know the backlight power requirement for that particular LCD, try a 150 ohm series resistor.
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Looks to me that your breadboard probably has a break in the +5v and ground lines, right where there is a break in the blue line next to the ground line. However, this may have saved you from burning out the backlight, since most LCD displays need a resistor in series with the backlight. If you don't know the backlight power requirement for that particular LCD, try a 150 ohm series resistor.

Thanks, I resoldered the connections, plugged it in, and tried again. It turned on. I'm going to put that resistor in though, considering you probably know much more about this than me!
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I added the resistor, and I can't even see if the backlight is on! Help?
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Bump
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I suspect that the resistor you are using is much higher than 150 ohms, or that you have connected it incorrectly. Can you post a photo? Also, if you can post a link to the lcd datasheet, I can determine whether a resistor is needed and what value it should be.
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I suspect that the resistor you are using is much higher than 150 ohms, or that you have connected it incorrectly. Can you post a photo? Also, if you can post a link to the lcd datasheet, I can determine whether a resistor is needed and what value it should be.

The resistor is brown, green, red, and gold. I got the LCD working by the Arduino tutorial, and i'm not using a resistor ATM. The potentiometer changes the contrast, while adding a resistor removes the backlight.
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That's a 1,500 ohm resistor. You need Brown, Green, Brown, not Brown, Green, Red.
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That's a 1,500 ohm resistor. You need Brown, Green, Brown, not Brown, Green, Red.
All I have is

Brown Green Red Gold
Brown Green Orange Gold
and
Orange Silver Orange Brown Gold
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Unfortunately, all of those resistors are too high to use as a series resistor for the backlight. [EDIT: the first is 1.5K, the second is 15K and the third is 3?K, I think you misread Silver because it doesn't make sense in that position.]

If you have a multimeter, you can check whether the LCD includes a backlight or not. Disconnect the wires to pins 15 and 16 of the lcd, then measure the resistance between each of those pins and the LED A and K connections (these are the two soldered connections at one end of the LCD). If you find that each of pins 15 and 16 is directly connected to one of the LED pins, then there is no built-in series resistor, and you risk burning out the backlight by not using one.
« Last Edit: January 14, 2012, 03:25:15 pm by dc42 » Logged

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