Simple LED screen signaling


10 posts
by Morgawr » Wed Jul 04, 2012 6:08 pm
Hello everyone, I bought this small screen
http://it.rs-online.com/web/p/products/532-6414/ (it's in italian but it's pretty clear)
a few days ago and it's going to arrive tomorrow.

My plan is to connect it to my raspberry pi and then send data from a program that parses common system utilities (like CPU load, uptime, ram available, connected users, etc etc) and display them on the screen so I can always check how my raspi is doing (it has no screen, I just use it through ssh).

My question is, I already have an arduino board lying around, what would be the best way to connect the screen to the raspi? My last resort would be to connect the pi to the arduino and send the messages to the screen through that, but it's quite hackish.
What I was interested in is connecting the GPIO pins to the screen and see what I can work from there, do you think it's doable? I don't have the screen now (yet) so this is all theoretical talk, however does anyone have nice guides to connecting the GPIO pins on the pi without risking of overvolting the board? (I have no problems with the programming side, I'm a programmer)
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by Mortimer » Wed Jul 04, 2012 6:32 pm
For those that are interested, the UK RS page is HERE.
Datasheet PDF is HERE
Image
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by Morgawr » Wed Jul 04, 2012 9:52 pm
Mortimer wrote:For those that are interested, the UK RS page is HERE.
Datasheet PDF is HERE
Image


Thanks! :) waiting for answers now. Don't need to be very detailed, just a point in the right direction (guides, examples, articles, whatever) would be a perfect start.
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by Mortimer » Wed Jul 04, 2012 10:13 pm
It's doable, but I would have thought that not only will it be electrically complicated, it will be quite a challenge to write the code too.

Wouldn't something like THIS be easier to work with:
Image

Datasheets : HERE and HERE
Would appear to be able to run from 3.3V signals, plus being I2C it can be controlled using a serial bus, rather than using half a dozen or so GPIO lines.
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by Morgawr » Wed Jul 04, 2012 11:58 pm
Mortimer wrote:It's doable, but I would have thought that not only will it be electrically complicated, it will be quite a challenge to write the code too.

Wouldn't something like THIS be easier to work with:
Image

Datasheets : HERE and HERE
Would appear to be able to run from 3.3V signals, plus being I2C it can be controlled using a serial bus, rather than using half a dozen or so GPIO lines.


Writing code is not an issue, it's something I find really fun so that'd be fine. How hard is the technical/electrical part? I'm still learning (I'm a CS major here, not an EE so I don't know too much).
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by reggie » Thu Jul 05, 2012 2:06 am
http://www.electronics-lab.com/projects ... index.html

These 8bit parallel screens are pretty much everywhere, look on sparkfun, adafruit etc. you'll probably find code examples, schematics etc. Arduino have some fairly mature libraries these days that can show you how to use the least amount of pins too, if it's got a compatible controller (it looks like it does) then you can use 8 data lines, 4 data lines or a shift register as you can see in the link above.
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by Morgawr » Thu Jul 05, 2012 7:56 am
reggie wrote:http://www.electronics-lab.com/projects/mcu/015/index.html

These 8bit parallel screens are pretty much everywhere, look on sparkfun, adafruit etc. you'll probably find code examples, schematics etc. Arduino have some fairly mature libraries these days that can show you how to use the least amount of pins too, if it's got a compatible controller (it looks like it does) then you can use 8 data lines, 4 data lines or a shift register as you can see in the link above.


This is perfect, I'm currently reading through everything. I received my LCD screen this morning, it's going to be an interestingly fun project, thanks!
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by reggie » Thu Jul 05, 2012 12:03 pm
You're welcome. I couldn't seem to find out which controller your particular LCD screen uses but it looks like it's a fairly regular one, so you should be ok with it as the principal of operation will be very similar.
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by Cybertimber2009 » Thu Jul 05, 2012 2:09 pm
Mortimer wrote:It's doable, but I would have thought that not only will it be electrically complicated, it will be quite a challenge to write the code too.

Wouldn't something like THIS be easier to work with:
Image

Datasheets : HERE and HERE
Would appear to be able to run from 3.3V signals, plus being I2C it can be controlled using a serial bus, rather than using half a dozen or so GPIO lines.
Hey Mortimer, would something like this work as well that you know of? http://www.adafruit.com/products/772
It uses the I2C connectors and 5V (http://ladyada.net/make/rgblcdshield/use.html)
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by Mortimer » Thu Jul 05, 2012 3:37 pm
You might need to get a level shifter to sit between the RPi and the display controller on the I2C bus, something like THIS or THIS.

Quite a useful guide : HERE
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