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Short story is I can't get my LCD to display what I want it to, nor will it respond to the commands I send to it.

Long story: I recently bought an arduino uno and a sparkfun serial 2x16 LCD. I think it is http://www.sparkfun.com/products/9395, or at least close. I've used the data sheet mostly successfully and have been able to do anything from displaying text to changing the lighting. Fast-forward to today. I don't recall exactly how it happened, but I think I made a program that worked then modified it slightly and started getting garbage on the screen.

Now it can consistently display the same garbage (depending on what I tell it to display) and I can't change the lighting or clear the screen. Even something simple won't work:

Code:
void setup() {
  Serial.begin(9600);
  delay(700);
}

void loop() {
 Serial.print("test");
 delay(1000);
}

I'm starting to wonder if something broke. Any suggestions?
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Is it a secret where you bought your serial LCD?
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Is it a secret where you bought your serial LCD?

No, but what difference does it make?
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Try a different baud rate - "Adjustable baud rates of 2400, 4800, 9600 (default), 14400, 19200 and 38400"
Start at 2400, and go up from there.

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Try a different baud rate - "Adjustable baud rates of 2400, 4800, 9600 (default), 14400, 19200 and 38400"
Start at 2400, and go up from there.

To my amazement, when set to 4800 it works.

But why does it work at 4800 now, when I've had it working on 9600?
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Try a different baud rate - "Adjustable baud rates of 2400, 4800, 9600 (default), 14400, 19200 and 38400"
Start at 2400, and go up from there.

To my amazement, when set to 4800 it works.

But why does it work at 4800 now, when I've had it working on 9600?

Either way, thanks for the help. It's much appreciated.
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Is it a secret where you bought your serial LCD?

No, but what difference does it make?

My crystal ball is not working. You will have to provide some details of what serial LCD you ARE using, not what serial LCD you THINK YOU MIGHT BE USING. The difference is "definitely getting no help" and "possibly getting the right help".
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Is it a secret where you bought your serial LCD?

No, but what difference does it make?

My crystal ball is not working. You will have to provide some details of what serial LCD you ARE using, not what serial LCD you THINK YOU MIGHT BE USING. The difference is "definitely getting no help" and "possibly getting the right help".
Your sarcasm is unnecessary. I listed what I think I have because this is the only thing I could find. And considering I can use the datasheet on the website for any of the command codes, it should be close enough.

The sticker on the back lists it as a ADM1602U-NSW-FBS/Z
When I looked it up online, I only found that page. And now that I have it fixed, it probably doesn't even matter anymore.
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Is it a secret where you bought your serial LCD?

No, but what difference does it make?

My crystal ball is not working. You will have to provide some details of what serial LCD you ARE using, not what serial LCD you THINK YOU MIGHT BE USING. The difference is "definitely getting no help" and "possibly getting the right help".
Your sarcasm is unnecessary. I listed what I think I have because this is the only thing I could find. And considering I can use the datasheet on the website for any of the command codes, it should be close enough.

The sticker on the back lists it as a ADM1602U-NSW-FBS/Z
When I looked it up online, I only found that page. And now that I have it fixed, it probably doesn't even matter anymore.

You understand straightforward question? Where did you get it? If what you think it is it exactly what it is, then why would it not work entirely? There's no point in asking/providing help if you the OP doesn't even provide what it is that you have and where you got it. smiley-cool
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Quote
And now that I have it fixed, it probably doesn't even matter anymore.
Well it will matter a lot to you if it happens again and it will matter a lot to someone else who may be trying to solve the same problem with his display.

All of the serial LCD adapters will typically work the same way when you send them ASCII codes at the correct baud rate. 

There is, however, little or no uniformity in terms of the special sequences that are needed to provide control over the display itself.  I am referring to the data you have to send to vary the way the cursor looks or where it is positioned, etc.

Some controllers (like yours) allow you to change the baud rate and others have a fixed baud rate.  The ones where the baud rate is changeable are more versatile and the others are easier to deal with.  Some (but not me, of course) would call them more idiot proof ....

It looks like the baud rate on yours got changed somehow. 


Don



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