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1  Using Arduino / Displays / Re: Turning an LCD Upside down, or LCDs with pins on the bottom on: July 31, 2014, 09:26:43 pm
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Is there a way to wire or program an LCD that will let me turn it upside down?

No.

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I've seen a couple of pictures of LCDs that had pins at both the top and bottom, or just the bottom,...

If you do find a source for an LCD module with the pins at the lower left make sure that you carefully check the datasheet.  The vast majority of those LCDs use a non-standard pinout and there are several different variations.

On the other hand the few LCDs that have pins at both the upper left and lower left seem to use the standard pinout (with pin 1 nearest the outer edge).


Don
2  Using Arduino / Displays / Re: Using the included LCD Display without libraries on: July 31, 2014, 09:15:36 pm
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Is this possible ...
Absolutely.

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...or is the library able to do some stuff what you canĀ“t do just with digitalWrite() and delay()?
No.  There's no magic to the library, it's essentially a bunch of digital writes and delays.

Follow the LCD Programming Examples link at http://web.alfredstate.edu/weimandn for heavily commented programming examples.


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You can look at the source code for the libraries.
I personally would rather work with un-commented assembly language code than plod through the convoluted web of Arduino library code.

Don

3  Using Arduino / Displays / Re: 16x2 goes blank after few hours. on: July 30, 2014, 01:47:20 pm
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Not so much really, its still going blank, takes like a day, day and a half  ...
I think you should be concentrating on what happened just before the display went blank or went nuts rather than on how much time has transpired since it last did so.

Don
4  Using Arduino / Displays / Re: SMH_7SD on: July 28, 2014, 09:32:52 pm
I give up, what's a SMH_7SD?

Don
5  Using Arduino / Displays / Re: connect act2004a lcd to uno on: July 28, 2014, 11:17:32 am
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I have a act2004a lcd that I'm trying to figure out how to hook up to a uno but can't find any info on how to do this.

Have you considered trying the Arduino tutorial: --> http://arduino.cc/en/Tutorial/LiquidCrystal


Don
6  Using Arduino / Displays / Re: LCD black boxes problem! on: July 27, 2014, 04:19:48 pm
I suggest that you rework your solder joints on the LCD header strip.

Don
7  Using Arduino / Displays / Re: LCD current draw on: July 24, 2014, 07:46:27 pm
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So even if i posted a back picture it wouldn't help to identify what model it is
You never know.  Someone might recognize it.

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Too less current? What is the current and voltage applied through a multimeter when looking for continuity or short circuits?
I'm not sure about digital multimeters but for the old analog meters the voltage and current depended upon which resistance range you were using.  Some meters even had different batteries for the higher and lower ranges.

I remember how some of my students would try to use an ohmmeter to test the fuses that were used to protect the laboratory microammeters.  Every one of the fuses that they tested, even the new ones right out of the box, tested bad.


Don
8  Using Arduino / Displays / Re: Displaying time on a 4x20 LCD on: July 24, 2014, 07:40:23 pm
Print leading zero

Code:
   
   if(second <10)
  {
    lcd.print("0");
  }
  lcd.println(second);
   

The lcd.println(...); is going to introduce extraneous characters.  Surely you meant lcd.print(...);

Don
9  Using Arduino / Displays / Re: Displaying time on a 4x20 LCD on: July 24, 2014, 07:38:09 pm
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... so if this has been answered, could someone point me in the right direction, I did have a 'Google' before trying here but had no joy.
This problem comes up quite regularly but coming up with the correct search terminology is not easy.

Here is one of the latest threads : --> http://forum.arduino.cc/index.php?topic=255213.msg1805883#msg1805883
And another: --> http://forum.arduino.cc/index.php?topic=254767.msg1802652#msg1802652
yet another: --> http://forum.arduino.cc/index.php?topic=118704.5


Don
10  Using Arduino / Displays / Re: LCD current draw on: July 24, 2014, 07:22:04 pm
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Unfortunately i've mounted the LCD and it's really difficult to take a back picture.
It would have been prudent for you to have taken pictures before mounting the device. 

I do this routinely for most of what I buy now.  It's a lot easier to get the model number for a washing machine I bought 6 years ago by looking at my computer rather than by crawling around on the floor with a flashlight and magnifying glass.


Don
11  Using Arduino / Displays / Re: LCD current draw on: July 24, 2014, 07:16:46 pm
As he is now using a new, unidentified, display there is no way to determine if his display is wired the same way as the ones you are familiar with.

I would question - what other possible way could there be for it to be wired?  It uses a HD44780 variant; they all work the same.   smiley-eek


It looks like you are saying that because they all work the same that all of the LCD modules use the same peripheral components on their pc boards and that they are all wired the same.

Although the vast majority of the modules using the HD44780 (and compatible) controller use the same external interface and the same instruction set this similarity does not necessarily extend to the pc boards on which the displays and controller are mounted.

My original point was that just because your particular module contains 10k of resistance back to VCC does not mean that all of them do.   


Don
12  Using Arduino / Displays / Re: LCD current draw on: July 24, 2014, 05:08:15 pm
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And you left the most amazing thing out, continuity check managed to lit the back light.. Sounds funny but it did

What is amazing about being able to light up an LED by connecting what is essentially a battery with a series resistor to the LED.  You have a 50% chance of lighting it up depending upon which way you apply the connections.


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Also, did anyone ask for the serial of this new LCD? No, so why should i post it? Is it so difficult to ask for it ?

I thought I did ask for it in reply #27.  Also, I guess you didn't get the hint in reply #33.

Don
13  Using Arduino / Displays / Re: LCD current draw on: July 24, 2014, 02:42:33 pm
It took 5 days and 23 posts before you revealed the actual part number of your original LCD.  We wasted a lot of time on that one.

It's been 2 days and 8 posts since you got your new LCD and we still don't know anything about it.  Is there some reason that you are keeping the identification of this new LCD from us?

Your last post has conflicting information about this new display which we cannot resolve for you or anyone else reading this thread.


"This display is wired exactly as the previous one and it works great."
conflicts with
"That tells me that this LCD's back light will turn on normally if i wire the back light pins 15-16."

Don
14  Using Arduino / Displays / Re: LCD black boxes problem! on: July 24, 2014, 09:59:10 am
Disconnect the wire from pin 5  (RW) of the LCD - which you presently have connected to pin 11 of the Arduino - and connect it to ground instead.

{Technical comment - wrong descriptor for that configuration!}


We are way beyond those problems if he has followed my outline.

Don
15  Using Arduino / Displays / Re: LCD current draw on: July 24, 2014, 09:53:25 am
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Contrast control works just as well with just a 5k variable resistor from Vo to the negative supply, since the module contains 10k of resistance back to Vcc and you only ever need to vary the contrast voltage a volt or two from the negative supply.

That would depend upon the specific display since they are not all the same.  As he is now using a new, unidentified, display there is no way to determine if his display is wired the same way as the ones you are familiar with.


Don
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