A few weeks ago I ordered some new parts for the table- mainly some el wire and a 3.2 inch resistive LCD touchscreen. Though the wire wasn't too big a deal to get to an acceptable place, the screen has been presenting some issues. I got it off of eBay, so I expected a couple snags- not the headaches I actually got. Turns out the screen uses 3.3v logic, while the Arduino I'm using for the table uses 5v. After nearly burning the thing out before realizing this, I switched over to my other Arduino (Seeeduino Mega) which can switch between 3.3v and 5v logic. After wiring it up (many different ways) and programming it I got... Nothing. Great.
I'm not sure if it was my wiring or the software (the "technical document" on the manufacturer's site is completely useless), but I eventually found a library at henningkarlsen.com that supported the screen. After getting it going on the Seeeduino, I set about moving back over to the Mega.
Which brought me back to the logic voltage issue. The problem with this library is that- though it works great- it requires a full 16-bit connection to the LCD controller (SSD1289), along with the control signals; that totals 20 connections. 20 connections means 20 voltage divider circuits, and 40 resistors to go with them. Keep in mind this is also before adding the extra connections needed for the onboard SD card slot and touchscreen. I know I can buy a pre-built Arduino shield for this instead, but thats admitting defeat.
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