Go Down

Topic: 4x8 character LCD, or two 2x8's? (Read 4101 times) previous topic - next topic

Piwoslaw

I've got an application which sends four parameters to the display. For testing I'm using a standard 2x16 character LCD, but space limitations won't allow a display that wide. The display can't be wider than 35-45mm, while 2x16's are twice that. I did a quick search for 4x8 LCDs, but no luck. Are they not produced?

What about using two 2x8 character LCDs? Could they be wired so that one displays both parameters from the 2x16's first row, and the other displays the second row? (In fact, they can display the four parameters in any combination.) Can the 2x16 be replaced by a 4x8 or two 2x8's by pure rewiring of the display leads, assuming that the device cannot be reprogrammed?

Thanks in advance.

runaway_pancake

Sending data to an LCD is sending data to an LCD.
What to do depends on what you want to do it with.
If you're hooked on using some 'library' or other and depend on its formatting functions then you might get tripped up.
"Who is like unto the beast? who is able to make war with him?"
When all else fails, check your wiring!

floresta

Quote
What about using two 2x8 character LCDs?

This would be an option.  It would require one more I/O line (seven instead of 6) for a standard parallel interface and you would need to invoke two instances of the LiquidCrystal library.  See the following thread for an example: http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1265969050

Don

liuzengqiang

Try oled displays. They are often small.
Serial LCD keypad panel,phi_prompt user interface library,SDI-12 USB Adapter

fm

You can use an I2C backpack and you would just use 2 IOs to drive both LCDs using the LCD library (also known as the New LiquidCrystal library - to Don's dispair :)). You would have to assign a different I2C address to each LCD, but that is about it.
Disclaimer - I carry an I2C backpack called the I2CLCDetraIO.
   

floresta

Quote
(also known as the New LiquidCrystal library - to Don's dispair)


Just to clarify things for the others, it''s not the use of the I2C library, it is the name of the library.

Don

fm

Sorry Don I should have said the name.
   


floresta

Quote
They got 2x8 displays..


But that's not what he is looking for.

Don

Piwoslaw

OK, so it seems that the 2x16 I measured happened to be one of the larger units, at least 10mm wider than most "normal" 2x16's. I looked at OLEDs, as liudr suggested, and they are slightly narrower, closer to what I'm looking for (though twice as expensive). Maybe I will be able to find a 2x16 that will just barely fit, without having to play with 4x8's, etc. Any ideas where I can look for narrow 2x16 lcds?

I am surprised that 4x8 character displays aren't available. I would imagine that it could even be used with a typical 2x16 library, just the 2x16's first row would spill over into the 4x8's second row, and so on.

Thanks everyone for your input:)

kucza83

Quote
But that's not what he is looking for.


Oups.. My bad..

How about a Nokia 5110 display... They are fairly easy to use. And they are cheap. 8)

http://www.sparkfun.com/products/10168

Docedison

You might look at COG displays... require more specialized handling and some different hardware but there was a device I worked with a couple of years ago was 4 X 16 and about40 cm. I found it at the Wescon convention and dealt directly with China for them unfortunately I don't have any of those details as I am retired... But a look at COG technology would only take a little time.

Doc
--> WA7EMS <--
"The solution of every problem is another problem." -Johann Wolfgang von Goethe
I do answer technical questions PM'd to me with whatever is in my clipboard

floresta

Quote
... but there was a device I worked with a couple of years ago was 4 X 16 and about40 cm.


That's pretty big.

Don

Docedison

Yes sorry about that 4cm - 40mm... about 1.6 - 1.7"... I do apologize, I still make mistakes in conversion... after 20 years working... I do apologize... Again. The COG types are a great deal smaller because ... among other things the driver board is not the physical support for the display. There are also bare LCD displays, ones that the user provides the driver IC for most are really easy to use... However (There is always one exception) all pins on the LCD must connect to the driver, 28 to 40+ depending on the # of things displayed. I used a 'glass' display 5 or 6 years ago, on an Intersil 7255 digital panel meter A/D and driver IC, total cost was about $3.50 at that time and DPM's were $10.00 each (basic 0 - 200 mV meter) in 1K quantities. The Best advantage was that i could and did place most of the project on the LCD board. It was a non contact measurement of Soil EC) and I had everything except the probe connector mounted on the display board.

Doc
--> WA7EMS <--
"The solution of every problem is another problem." -Johann Wolfgang von Goethe
I do answer technical questions PM'd to me with whatever is in my clipboard

Go Up