I bought a display module marked "TFT-320QVT" on deal extreme awhile ago, it's go the 2x20 connector and the SD card reader and resistive touch on the board. It is NOT a shield, and not the variety with the clock on it.
This week I finally got the ambition to go look for specs and drivers, and have hacked together a shield adapter for it, based mainly on the "ITDB02 MEGA shield v1.1" kit, since it appeared to use the UTFT common library and was geared to use series resistors to level convert. (I don't have any level converting SOPs to use) I build up a shield using copper eyelet perfboard and wired things all together over the last few evenings. (you don't want to see it... it looks pretty ugly... functional, but ugly)
After careful testing to make sure my wiring matched that of the IDTB schematic and the level protections were working satisfactorily, I hooked it up and am now trying to get a demo running. The UTF demo I am working with is UTFT_Demo_320x240. I cross referenced the pins and found that the initializer should be something like:
UTFT myGLCD(ITDB24E_16,38,39,40,41)
I was somewhat pleasantly surprised to find that 38-41 are the numbers almost everyone is using in their init, so I assume I'm on the right track and at least haven't done something catastrophically wrong like mirroring a connector. Unfortunately, I've been unable to get anything except a solid grey screen that appears at power-on. I've tried the following controller selections:
HX8347A
SSD1289
ITDB32
ITDB32S
GEEE32
ITDB24E_16
None of them produce any results. Several sources online suggest the controller is either a SD1289 or a HX8347-A. I would like to assume I have a functional panel and have wired the shield adapter properly, and am doing something elementary wrong or have yet to try the correct model in the constructor. Is there any useful way to tell what controller I need to select? The LCD is somewhat bonded to the card it's on, and I don't feel comfortable trying to pry it up as it's not acting even slightly movable.
I'm also assuming I can't fry anything by selecting the wrong driver. There are two "unprotected" pins used, that do not do level conversion, but those are the SD_OUT and the D_IRQ, and those are both outputs from the module. I assume if they get HIT with 5 they'll toast, but changing the constructor model shouldn't alter the pinout and cause the mega to go HIGH on them? And is it necessary to fully power cycle the setup to reset the LCD after I try a model id and it doesn't work? I've just been changing the model and uploading again to test the next one. I suppose I can go through the entire list...
Oh and FWIW, someone in another post was asking what the jumper pad is for on this display module. It jumps the IN to the OUT on the 3v3 regulator, for if you are going to supply the panel with 3v3 instead of 5v.
Heading to bed now. I decided to put the scope on a few pins to see what the levels looked like, and I'm somewhat alarmed to see what looks like 5v digital signals on the digital input pins. All of these pins have a 10k resistor in series between them and the arduino. I was expecting the diodes on the gates to easily clamp those voltages to 3v or whatever their max is, and was therefore expecting voltages on the LCD side of the resistors to be in the 3v range. But the digital square waves are exactly one division high on my scope when set to 5v/div. So... was I unlucky enough to get a module with a controller that doesn't clamp, and have fried it?