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Mini LCD screen

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Encryptor:

chrimeg

I found this link. It look like they hacked a key chain digital photo frame to play video.

http://spritesmods.com/?art=picframe


Encryptor

chrimeg:

I've also located the link for hacking a mini lcd screen into a mouse.

Looks very promising.

Hopefully someone with an electronics background can also come up with solutions.

The last link that was sent also looks like a very good hack. Unfortunately it only runs on linux right now.

Here is the link I found: http://metku.net/index.html?path=mods/loginoki/index_eng

MonMotha:

The really tiny LCDs for cell phones are generally SPI interfaced (including the one you linked).  They often have little to no timing requirements other than a maximum frame rate.  You may be able to get acceptable performance by bit-banging SPI off a parallel port.  Don't expect more than maybe 2-5FPS doing this, but it may be acceptable for your usage.  If you need something faster, there's lots of uCs out there with USB interfaces and SPI masters.  These will let you run the LCD pretty much as fast as it can be run.  You can buy bare LCDs of this nature from Sparkfun in single quantity.

Some higher end small panels, especially in QVGA size, are so-called "smart panels".  These have a framebuffer on them, so you don't have to constantly scan in video data like you would to a conventional monitor.  You can do random access to them as you please.  Again, this could be hooked up to a parallel port (esp. in EPP mode) fairly easily with just some "glue logic" (74 series or a small PLD) or again a USB enabled uC with a local bus and some suitable firmware.

Most LCDs in picture frames and such are standard dumb LCDs that need to be constantly scanned.  For this, you need a framebuffer which means RAM.  Your parallel port probably can't run fast enough for VGA (best you can really pull on a modern PC is usually about a 10MHz cycle rate in SPP mode) to keep up with the required pixel clock, so you'd need some external hardware for that, but you may be able to manage QVGA with a lot of CPU overhead.  The hardware isn't complicated (some RAM and a small CPLD will do to glue it to a parallel port), but it isn't going to be "plug and play" to a PC.  Again, a small uC, some RAM, and a PLD to handle the LCD interface wouldn't be too expensive, but might be a fair bit of design work for a one-off application.  I've done something similar before on an FPGA.

Ginsu Victim:

I had to stop reading that because I was starting to feel more and more dumb as I went along...

MonMotha:

Heh.  I do this stuff for a living :)

If you want something hackable, take a look at portable DVD players.  Many of them are nothing more than set-top DVD player system-on-chips paired with a slim DVD reader and an LCD with a daughterboard to accept S-Video or composite from the system on chip (since that's all they often output).  Pretty easy to hook up to: apply power and analog video.  Quality is usually kinda bleh, though.  The scalers and such aren't really designed for graphics and text but rather the "softer" edges of TV and movies.

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