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USB Graphical LCD Thoughts


New member
Okay, here are my thoughts on what would make a good USB graphical LCD unit.

Firstly, the only CF LCDs I would suggest for the job would be the CFAG240128D-FMI-T and the CFAG320240C-FMT-T

Some form of touch screen would be a really great alternative to the 633's buttons

The 633's Fan control & temperature sensing would also be a great addition, plus it's another unit that would use the WRDOW17 temperature sensors. I wouldnt bother much with the 633's ATX functionality.

Being able to download updated firmware into the unit would be a definate plus, it's a shame this feature didn't make it into the 63x series.

A non-volatile memory with enough storage to be able to store at least 8 framebuffers that could be quickly blitted to the screen with a single command would not only make updating the screen easier, but would also relieve some traffic on the USB bus, and also would possibly relieve the host PC some since it wouldn't have to generate bitmaps to upload all the time.
Expanding on this idea, a command to to partial blits from the unit's nvram to the display's frame buffer would be great for things like touch-screen buttons that change somehow when pressed, complex bitmapped fonts, etc.

A simple drawing command set would be beneficial, so you could do line drawing without needing complicated host-side code to generate bitmaps and upload them on the fly.

A way to read the frame buffer back from the display to the host would be handy aswell for being able to do LCD screen captures.

The USB interface itself need be no more complicated than the USB/COM setup the 63x series has, infact this would be really easy to write software for, since it's a COM interface that both Win32 and Linux can handle, and it also runs at the USB speed completely ignoring the baud rate that gets set by the software so you get 12mbps to the unit. Also, I honestly think that a native RS232 interface would be too slow to be practicle for handling the graphics of the unit, but it might be a handy thing to have for updating firmware if doing that through the USB prooves to be too complicated.

They are my thoughts, feel free to use them or throw them aside, but I for one would buy one of them!!

Robert 'Heffo' Heffernan
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