You'll note he's a high-school age student attempting self-education. I agree that, for his robotics project, and with the experience in coding that he's had, he'd be WAY better off with a PC in PC-104 format than with any microcontroller.

His initial query, however, indicated that he's also interested in learning about microcontrollers, which that small single-board PC-104 type is, but also on a budget, which is probably implicit in the age-group of which he's a member.

If he's willing to learn about microcontrollers, I'd favor making it as easy as possible for him. AVR and Arduino won't do that. First of all, AVR comes from Atmel, and nobody else. There are no other options. I haven't even bothered to look up where Arduino comes from, but if it's not as many sources as 805x-core MCU's, I'd find that of little interest as well. No competition, no interest on my part.

When ATMEL's 805x's let you down, you can always go to one of the other manufacturers. Philips, Dallas, SiLabs, and several others can fill in. Many of 'em cost a dollar or so. Even the costly ones don't cost much. What does a minimal 40-pin AVR cost?

RE