This is an interesting discussion because I'm also trying to put togethe an ARM-based device with a 320*240 TFT. It is a hobby project but I do ai to produce a number of them if all goes well, so I need a cheap design an I don't want to use anyone else's modules. Having spent many hours lookin at ARM devices from Sharp, NXP, Atmel and so on with integrated controller and ended up rejecting all of them either because they're BGA, or because can't get the devices easily or have fear of them becoming obsolet (especially Sharp) or various other reasons, I have decided to fall bac on the old faithful solution which is to use an Epson controller togethe with an ARM that has an EMI.
In fact my prototype at the moment is an STR710FZ2T6 together with not a EPSON device, but instead a Solomon SSD1906. I don't think that anyone ha mentioned the Soloman parts yet but they appear to be the Epson parts tha have been rebranded and repackaged. Maybe someone can tell me more abou this.
I went for the Solomon device because it's easy to get hold of in the U to make a prototype. Rapid Electronics and RS over here actually stock it To get an EPSON S1D device I'd have to make an expensive order from Digike in the US.
The STR710, SSD1906, plus the flash and RAM is quite a nice cheap solutio I think.
I have personally already worked with the EPSON S1D devices in the past by the way. Several years ago where I used to work I did a design usin the S1D13705. I found it really easy to use. I didn't use any of EPSON' software. I just used the datasheet and wrote my own routines and so on That design used a PIC18F8720! I guess the slow response and blurryness o the STN panel we used sort of disguised how slow the graphics were :-) Tha product is still being sold by the company, so maybe I could try to sel them an improved ARM version...
Now for a question:
For those who have already used an EPSON or similar device with an AR controller, what kind of speed of graphics can one achieve assuming, say anything from a 320*240 to a 480*640 VGA panel? Assuming an ARM7 an S1D13705 or similar, can anything near to streaming video be achieved?
Cheers
Trev