I tend to agree that this is possible as well, but an investigation into this some time ago turned up less promise than I had hoped for. One of the problems is the lack of suitable, well supported display controllers for this type of project. There are a group of specialized controllers made for low-end monochrome displays, another group for cell phones and PDAs, and then of course, those made for PCs. In between though, there should ideally be a group of controllers with the ability to drive somewhat larger/higher resolution displays, offers an 8-bit-friendly interface, and requires a bare minimum of support components. Unfortunately, this type of controller does not really seem to exist. Epson made (and still makes) some devices of this type, but does not seem to be supporting them particularly well (i.e., evaluation boards no longer available).

And of course, once you get the hardware, there is a significant software challenge that remains. Arguments of computational complexity for an 8051 derivative CPU aside, desigining and implementing a graphics API for the controller is a daunting task. There are probably three levels of software involved: a low level interface to the raw hardware, a set of graphics primitives that runs on top of that, and a high level interface (i.e., draw_text_box(text, location, color)). I was not interested in writing all this, so I looked around, and found emWin. It pretty much seems to do everything one would want in this type of application. Unfortunately, the price put it quite out of the question for a small project.

So, in the end, I ended up going to a PC-based SBC solution. The per-unit price is higher, but the up front cost, both in terms of tools required and design time, is much, much lower.

--Sasha Jevtic