I am interested in building haunted house animatronics. I am trying to settle on a microcontroller family to use, because I know I will be reluctant to switch once I get started.
By reading various robotics books and microcontroller comparisons on the Internet, I have narrowed down my choice of microcontroller families to either: (1) the AVR family, or (2) the 68HC11/68HC12 family. (The PIC family seems a little too low-level, and the 8051 chips seem a bit quirky.) I am having trouble deciding between the AVR and the 68HC11/12 lines.
I'm wondering if there are any former 68HC11/12 users out there who switched to AVR, who could tell me why they switched. Or vice versa. I have read several places that there seems to be a groundswell of people switching to AVR chips. But David Cook, whose robotics books I tremendously admire, strongly supports the 68HC11/12 family.
The microcontroller attributes that are important to me are: (1) low cost (preferably under US$5 chip in single quantities); (2) large range of processors in the family, for both lower-end and higher-end applications; (3) strong supporting community offering aftermarket products, programmer boards, example software, etc.; (4) lots of I/O lines (12 or more would be nice); (5) on-board PWM capability to control servos; (6) on-board UART and SPI features; (7) A-to-D converter; (8) a built-in clock would be nice; and (9) 1K of RAM and 4K of some sort of static program storage.
Using Digi-Key's web site to look up comparative pricing, it looks like an AVR microcontroller with the above types of capabilities runs about $4 in single quantities, whereas a 68HC11/68HC12 with similar capabilities runs about $17 in single quantities. That is a big price difference. I think I must be misunderstanding something. Low cost is not an overwhelming factor, but it's fairly important to me, because some of my projects might use a lot of embedded microcontrollers.
I know I'm kind of opening a can of worms here, since everyone has their own reasons for liking a particular microcontroller family. I wouldn't leave such an open-ended question here except that I've been having a devil of a time figuring this out, even after many Google searches and reading many web sites. Please, if anyone has any thoughts on AVR vs. 68HC11/12, I'd very much appreciate hearing them. Many thanks for your time!
-- Randy Forgaard