Did I fry my lcd?

I bought an LCD from Maker Shed got it up and running on my Arduino and I was one proud papa!

I then needed to rearrange my breadboard to fit more components and after re-wiring my lcd stopped working. It lights up but I can’t adjust the contrast to display the row of blocks.

You’re probably thinking “Deeg you knucklehead, you’ve wired it wrong” so I’ve included a shot of the board with the wiring (see next post). Is it possible that the lcd is fried? Is there some other test I can run?

The power supply is a 9v 500ma wall wart. I’m using the arduino to run other functions (i.e. controlling a fan via pwm) so I don’t think there’s anything wrong with it. I’ve used my multitester to verify that the pot is working as expected (and I’ve tried other pots).

LCD: http://www.makershed.com/ProductDetails.asp?ProductCode=MKAD15

Wiring: http://www.flickr.com/photos/76246285@N00/4785413208/in/set-72157624474579682/

What power are you using? As in 3.3v, 5v, or Vin? It says it should be 5v in... Also, are you powering more components, or just having more on the breadboard?

Your photo shows that no power (+5V/GND) is connected to the LCD (pins 1 and 2).

http://www.ruggedcircuits.com

What power are you using? As in 3.3v, 5v, or Vin? It says it should be 5v in... Also, are you powering more components, or just having more on the breadboard?

It's not apparent from the picture but I'm using 5v/gnd from the arduino. The twisted red/black lines from the arduino pins go off the picture then come back and connect to the left side of the breadboard. I plan on powering more components (thermistors) from the arduino but I can't get the LCD working even with no other components (the other stray wires on the arduino in the picture are not connected to anything).

Your photo shows that no power (+5V/GND) is connected to the LCD (pins 1 and 2).

According to Lady Ada's LCD tutorial I'm supposed to connect 5v/gnd to pins 15 and 16. Unless I've missed something obvious my circuit should look exactly like her circuit.

From the Makershed site:

To use, connect pin 1 (GND) to ground, pin 2 (VDD) to +5V, pin 3 (Vo) to the middle of the pot, pin 4 (RS) to Arduino pin 7, pin 5 (RW) to ground, pin 6 (E) to Arduino pin 8, leave pins 7-10 disconnected, pin 11 thru 14 (DB4-DB7) to Arduino pins 9 thru 12, pin 15 (BL+) to +5V and pin 16 (BL-) to ground.

So your connection to pins 15 and 16 are really just to power the backlight. You HAVE to connect pins 1 and 2 as described above to power the logic.

http://www.ruggedcircuits.com

Oy, I'm a moron. I forgot that it requires two power inputs (which is clearly labeled in the tutorial and I obviously followed it the first time). Thanks for the help RC and for not pointing out that I am, indeed, a knucklehead. (I am just smart enough to figure that out on my own).