Arduino LCD problem Help!

Here is the problem : http://www.youtube.com/watch?v=sTDKdQ2TDqo

it does that when i click reset. It's been doing that at the beginning and ive already restarted everything about 4 times. I followed the official arduino LCD tutorial to hooking it up. Any suggestions?

Any suggestions?

For starters we need a stationary photograph of your connections and a cut/paste copy of the code that you actually used (not a link to the code that you think you used). Also when you get it working don’t be surprised when you see an offset on lines 3 and 4. The LiquidCrystal library does not handle 16x4 displays correctly.

Don

floresta:

Any suggestions?

For starters we need a stationary photograph of your connections and a cut/paste copy of the code that you actually used (not a link to the code that you think you used). Also when you get it working don’t be surprised when you see an offset on lines 3 and 4. The LiquidCrystal library does not handle 16x4 displays correctly.

Don

There is a thing called pause u know. But either way heres the page I used to determine the pin connections I followed it 100% so no need for a photo.

heres the link Arduino Tutorial - connecting a parallel LCD

heres the code too:

/*
  LiquidCrystal Library - Hello World
 
 Demonstrates the use a 16x2 LCD display.  The LiquidCrystal
 library works with all LCD displays that are compatible with the 
 Hitachi HD44780 driver. There are many of them out there, and you
 can usually tell them by the 16-pin interface.
 
 This sketch prints "Hello World!" to the LCD
 and shows the time.
 
  The circuit:
 * LCD RS pin to digital pin 12
 * LCD Enable pin to digital pin 11
 * LCD D4 pin to digital pin 5
 * LCD D5 pin to digital pin 4
 * LCD D6 pin to digital pin 3
 * LCD D7 pin to digital pin 2
 * LCD R/W pin to ground
 * 10K resistor:
 * ends to +5V and ground
 * wiper to LCD VO pin (pin 3)
 
 Library originally added 18 Apr 2008
 by David A. Mellis
 library modified 5 Jul 2009
 by Limor Fried (http://www.ladyada.net)
 example added 9 Jul 2009
 by Tom Igoe
 modified 22 Nov 2010
 by Tom Igoe
 
 This example code is in the public domain.

 http://www.arduino.cc/en/Tutorial/LiquidCrystal
 */

// include the library code:
#include <LiquidCrystal.h>

// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(7,8,9,10,11,12);

void setup() {
  // set up the LCD's number of columns and rows: 
  lcd.begin(16, 2);
  // Print a message to the LCD.
  lcd.print("hello, world!");
}

void loop() {
  // set the cursor to column 0, line 1
  // (note: line 1 is the second row, since counting begins with 0):
  lcd.setCursor(0, 1);
  // print the number of seconds since reset:
  lcd.print(millis()/1000);
}

You have:

 lcd.begin(16, 2);

Your display is 4 x 16 lines. So that is the first problem. The letters I saw on the screen (and pausing didn't totally help) were:

S s C # 3

Interestingly, the hex codes for those are:

53 73 43 23 33

There is a definite pattern there. Perhaps one of the data lines is not wired correctly, or the pins are not soldered on completely.

[quote author=Nick Gammon link=topic=53893.msg385495#msg385495 date=1298957695] You have:

 lcd.begin(16, 2);

Your display is 4 x 16 lines. So that is the first problem. The letters I saw on the screen (and pausing didn't totally help) were:

S s C # 3

Interestingly, the hex codes for those are:

53 73 43 23 33

There is a definite pattern there. Perhaps one of the data lines is not wired correctly, or the pins are not soldered on completely.

[/quote]

hmm ill see if that could be the case, but I soldered them perfectly and everything

[quote author=Nick Gammon link=topic=53893.msg385495#msg385495 date=1298957695] You have:

 lcd.begin(16, 2);

Your display is 4 x 16 lines. So that is the first problem. The letters I saw on the screen (and pausing didn't totally help) were:

S s C # 3

Interestingly, the hex codes for those are:

53 73 43 23 33

There is a definite pattern there. Perhaps one of the data lines is not wired correctly, or the pins are not soldered on completely.

[/quote]

nope didn't help, everything is connected fine , i even connected the lcd to a different part of the breadboard incase the connections where faulty.

Let's put it this way ... Earlier today there was a similar question (a couple of threads down) and after a lot of troubleshooting the original poster said:

Alright, that was it......I guess there was a cold joint in there because when I stuck the LCD back into the breadboard after re-melting all the solder joints, it worked!

So, maybe resolder?

[quote author=Nick Gammon link=topic=53893.msg385517#msg385517 date=1298961646] Let's put it this way ... Earlier today there was a similar question (a couple of threads down) and after a lot of troubleshooting the original poster said:

Alright, that was it......I guess there was a cold joint in there because when I stuck the LCD back into the breadboard after re-melting all the solder joints, it worked!

So, maybe resolder? [/quote]

nope, i did that now and no luck, I specifically soldered them perfect the first time too but 2 times didnt work either. I think Ill just try a smaller LCD, we have like 10 LCD,s in my class that my teacher didn't even know about and he lets be borrow them.

There is a thing called pause u know

Pause doesn't help when one wants to enlarge the picture to examine the connections and soldering.

I followed it 100% so no need for a photo.

I've heard that before. You asked for help and I told you what was required.

I specifically soldered them perfect

From what I can see in your video the soldering is horrible. You've used enough solder for all 10 displays that you have.

Your display is 4 x 16 lines. So that is the first problem

It's not a problem with the current version of LiquidCrystal. It doesn't matter what you use for the argument as long as the second value is greater than 1.

I saw the same pattern when I looked at the data. You really have to look at the binary and remember that the upper and lower nibbles go out on the same wires. I agree that there is most likely something wrong with one or more data lines.

We know that the LiquidCrystal library is good and since his wiring was done 'perfectly' then the display must be working. I guess we are done.

Don

floresta:

I specifically soldered them perfect

From what I can see in your video the soldering is horrible. You've used enough solder for all 10 displays that you have.

I second that. I call them kisses.

liudr:

floresta:

I specifically soldered them perfect

From what I can see in your video the soldering is horrible. You've used enough solder for all 10 displays that you have.

I second that. I call them kisses.

actually both of you are mistaken. You just can't see it properly in the video. The soldering IS perfect. Turns out it was the LCd, I switched it for a different one and it works lovely.

You also soldered the new lcd? So there is still chance you didn't do the first one correctly. You put too much solder on all the pins. It's obvious even from the poor video. I would use less than1/8" (2mm) length of 0.032" diameter solder for each LCD junction.

actually both of you are mistaken. You just can't see it properly in the video. The soldering IS perfect.

Have you shown it to your teacher and asked for his evaluation?

Don

liudr: You also soldered the new lcd? So there is still chance you didn't do the first one correctly. You put too much solder on all the pins. It's obvious even from the poor video. I would use less than1/8" (2mm) length of 0.032" diameter solder for each LCD junction.

ok I soldered the LCD 100% fine, now you are just trolling me sir.

floresta:

actually both of you are mistaken. You just can’t see it properly in the video. The soldering IS perfect.

Have you shown it to your teacher and asked for his evaluation?

Don

sir the new LCD has been soldered by me and it works fine. The solder work was fine I don’t care about this issue anymore

I don't care about this issue anymore

That's a pretty self centered attitude If you check back on the previous forum posts you will see that Dr. Liu and I are far from trolls. We have helped dozens or perhaps hundreds of LCD beginners get their devices working. My displays are older than you and my programs were working (on other processors) several years before you were born. Since my devices are correctly connected and my programs are written properly, they work, every time. Dr. Liu is still teaching so I am sure that he gets plenty of input from his students. I retired at about the time you were running around in diapers so I no longer have that source. We both rely on feedback from those we help to build up our knowledge base from which we can help others. If you will take the time to go back and find out why your original display does not work, and then tell us, we can use that knowledge to help others in the future. I cannot remember previously seeing the particular display that you got so this one is especially interesting to me.

Don

floresta:

I don't care about this issue anymore

That's a pretty self centered attitude If you check back on the previous forum posts you will see that Dr. Liu and I are far from trolls. We have helped dozens or perhaps hundreds of LCD beginners get their devices working. My displays are older than you and my programs were working (on other processors) several years before you were born. Since my devices are correctly connected and my programs are written properly, they work, every time. Dr. Liu is still teaching so I am sure that he gets plenty of input from his students. I retired at about the time you were running around in diapers so I no longer have that source. We both rely on feedback from those we help to build up our knowledge base from which we can help others. If you will take the time to go back and find out why your original display does not work, and then tell us, we can use that knowledge to help others in the future. I cannot remember previously seeing the particular display that you got so this one is especially interesting to me.

Don

first of all Don, that talk about my age and diapers and whatnot is irrelevant to this post and hinders my respect towards you (even though I don't know you). That kind of talk is unnecessary and frankly, a bit arrogant. . Second of all the display did not work because it was faulty. I do not have the time or interest to keep looking at it and see what is wrong, I looked at it many times staring at the solder points. There where no shorts or breaks in the solder, I even ruled out the possibility of a faulty breadboard. And to the people who tell me to get it evaluated by my teacher, in all honesty to him, he doesn't know very much what he's doing. The arduino isn't a class project we are doing, I do it on my own time. I have soldered enough circuits before that I know when a solder point is bad or well done. Just because I am a beginner in arduino doesn't mean I am a beginner in electronics. If you want to know more about the old LCD then all I can say is the back of it had 4 chips instead of 2 like the one I'm using right now. Like I said before I have fulfilled what I was going to do and everything is fine now, I don't know why this topic is still getting posts.

It looks like I got your attention.

I do not have the time or interest to keep looking at it and see what is wrong ...

You did ask for help when your display wasn't working properly. Those of us who do have the time to help others rely on getting information from as many sources as possible. Right now you have a device with a problem that hasn't shown up before but may very well show up again in the future. By taking a few minutes of your time now to find out the problem you may help someone else save a lot of time in the future.

Second of all the display did not work because it was faulty.

I doubt that your display was faulty since it was able to display legible information at every location on the screen. Faulty displays, if they work at all, tend to have some screen locations that are always dark and/or other areas that are always clear. Your type of problem is virtually always due to a problem in getting the data from the host microcontroller to the LCD board.

If you want to know more about the old LCD then all I can say is the back of it had 4 chips instead of 2

Here is a perfect example of how a seemingly trivial piece of information can be important to someone else. I have never possessed or used a 16x4 display and I assumed that they had 5 chips like the other 4 line displays. Now that I think about it, and knowing a little bit about the workings of the controller, that makes sense. It also validates my theory on how the internal memory and the memory addressing is structured and why the LiquidCrystal library does not position the characters correctly on lines 3 and 4 of this device.

Don

polishdude20:

If you decide that you want to help could you please hook up your 'faulty' LCD module and write a simple program that clears the screen and then sends exactly 80 printable ASCII characters to the display and then stops. I usually start with the first displayable character which is the exclamation point (0x21). A photograph of the resulting screen will help me try to figure out what is wrong by comparing the binary codes for what was sent to the binary codes for what was displayed.

Don

polishdude20,

I honestly wanted to help any way I can but I can feel your self-centered ego from miles away. If I wanted to understand what went wrong with my device, I'd be more open to suggestions and what not. Not everyone, especially floresta, who has worked quite arduously on this board, or me or others has responsibility to help you or anyone else. We all assume the best manner from every inquiry maker but we can certainly take some hits. The way you described your teacher is interesting. You think you know more than him but to me those that know more than I do all tend to be more humble when it comes to admitting knowing stuff. I hoped that you would find what went wrong so that previous display didn't work so others can learn from some mistake. Let's just drop this discussion and say you got a bad display. Good luck to your future projects. I won't be very helpful to you anyway.