Driving Sharp LQ121S1DG11 Colour LCD

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Hi

I bought "by accident" a 12 inch Sharp colour lcd labeled LQ121S1DG11.
Has anybody experience with this monster ?
What would be a working strategy to use this display?
An AVR i am afraid will be overloaded , but at least the AVR should send the data to the lcd controller.

I was looking for a small graphical colour lcd on ebay, while stumbling over this part. I place a bid, but did not expect to win.

I would like to use it in a controlling app for my robots, to diplay the data I recieve from them and to send controll strings.

Cheers
Rubi

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Rubi wrote:
Hi

I bought "by accident" a 12 inch Sharp colour lcd labeled LQ121S1DG11.

Thats a laptop screen. :shock:

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And laptop screens don't include a controller... an AVR does not have the power to control this display I'm afraid.

800x600x60x3 ~ 83 megabytes of data needed per second assuming 24 bits per pixel at 60 hertz refresh rate.

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There are some circouts around for an EPSON lcd controller.
Unfortunatly I cant find them anymore and I dont know if the controller is sufficial for this amount of data.
I think they are called SED...

RobSki wrote:
>>>
Thats a laptop screen. Shocked
<<<

I know, I already stated this is a monster version of an lcd,...

Cheers
Rubi

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As a starter try SiD13705F00A
This is the bottom end epson controller I suspect no good for your application but will lead you in.

Keep it simple it will not bite as hard

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TFT displays need a datastream of usually three 6-bit pixel values (r,g,b) at a rate of the order of 35-40MHz. Plus clock & 3 sync signals (HS,VS,Data enable)
Supply and logic levels are usually 3.3v (plus the HV supply for the backlight)
This is beyond the capabilities of the AVR to drive direct, but is relatively easy from a small CPLD of FPGA, which can either update the display from an attached RAM chip, or make patterns etc by 'on-the-fly' generation of data based on X/Y address counters.
You may just be able to get some pretty patterns out of an AVR by driving at a low frame rate but you'll be pretty limited as to what you can do.
A complication is that later panels multiplex the 18 bit pixel data, sync and clocks into 4 high-speed LVDS channels. However panels of the 800x600 era tend to use a discrete LVDS receiver chip, so you can either use the corresponding transmitter chip, or take the receiver chip off and feed in the parallel data direct.

Here is some data on your panel :
http://support.advantech.com.tw/Cservice/LCD.nsf/f99b88c84af1eeff482565ec000759ea/e86ed64623eeeafd482568a800285ea8?OpenDocument

There is some info and links to some TFT panel data near the bottom of my page at www.electricstuff.co.uk/ektapro....
Specs of similar-sized panels are generally similar - for a given panel size, the main difference is whether the interface is LVDS or Parallel (latter often termed TTL), and sometimes some minor differences in sync timing, so you can often use the datasheet of a similar device to get going, as datasheets can be hard to find.
Don't run the panel for extended perions without clock or sync as this will cause electrolytic damage.