Hi again !
while doing my search on OLED I stumbled on a massive source of cheap 7" LCD
they are picture frames, they cost with shipping to the USA about 40$ USD
the exact cheapest one I could find was 37.90$ with shipping
I think they are very good candidate for salvage because they are such mass produced items the LCD in them will be available for a long time
the resolution is Wide QVGA 480x384 probably 16:10 aspect ratio
they have other interesting parts, the specific model I am looking at also has
1 female USB-A connector
1 female 3.5mm headphone jack
1 female AV jack that is probably 2.5mm , I assume it comes with a 2.5mm to RCA adapter cable too
there’s a SD/MMC card holder
1 or 2 speakers
a small power supply input 120V/240V output 10VDC 1.5A
and a housing for your arduino project
on the board there are probably a few interesting bits that can be reused, maybe a small amplifier for the speaker/headphone and maybe something else
ebay link (there are tons of these, that’s just the cheapest one I could find)
So what are you going to do with the 7" LCD? Have you been able to connect it to the Arduino and draw or show text on it?
Same question here, hacking it or just using it as it’s intended for? Just my opinion, You may spend a lot of time trying to find out how to control it and still have occasional problems with it after a while. I would buy an LCD board instead, less destruction and more using it. BTW, TJMAXX at my location has even cheaper ones in smaller sizes for less and Target has many toys with dot matrix displays. I almost wanted them like a child but eventually walked away after getting suggestions from experienced members here.
I ordered one, I'll know how it can be interfaced when it gets here
I have a willem programmer so maybe I can re-use it's controller or get some info on how to control the LCD
I think the 7" VGA LCD are probably the cheapest per inch² display for use in projects
I don't have a specific use for it now but I prefer to source parts way in advance, but I can see this is a perfect candidate for a LCD gauge cluster for use in a car, I have a few pontiac firebirds and the dash is just perfect for this size, I can probably fit two of them side by side after I cut out the ugly gauges currently in it
I also think that this with a 7" touch membrane would make a very good HVAC control interface (which is the next project I'm doing when I'm done on my current contract.. well that and the big shed I'm building) the heating system will be awesome.. can't wait to begin :)
Typically, VGA screens require that the controller manage the data for each pixel. The Arduino does not have near enough memory for that task. So, an external controller is necessary. Hopefully you will be able to re-purpose one that currently is used to drive the screen, but I have my doubts. I hope I am wrong.
or get some info on how to control the LCD
Yeah, good luck on that.
I also have my doubts about this project. Just as you need a graphics controller chip to use a laptop screen as a monitor, you will need something besides an arduino to interface with a vga monitor. I suspect you would have to do a lot hacking with the code on the controller. But best of luck!
I think this will be a very difficult interfacing task. The LCD in a picture-frame is made to work directly with the custom chip on the PCB. You may find that there's no (public) documentation for the interface. You will most likely need a much more powerful CPU than the Arduino to generate graphics for this type of LCD.