It's weird, that... I suspect I could rustle up
something 'traditional'
around
a Z80/6502, ROM, RAM and some decoding - but my brain just doesn't cope
well
with single-chip 'black boxes' such as PIC-based widgets. I really don't
know why!
Jules, I work developing hardware for a living, and I'll tell you
something: If you are used to Z80, you'll have a hard time using a PIC. But
an AVR will be easy to you to swallow.
When I began with microcontrollers, I used 8751. It was a more-or-less
easy transition, since they just looked like any intel assembly you are used
to. BUT when progress came, and I had to use a PIC, I spent **MONTHS**
trying to swallow the different approach of PICs. I was saved when I found
the AVR that is easier to program and prototype. One of the many things that
appeals to me is that a 74'244 and a parallel port is all you need to
program ANY of the AVR lineup in circuit (and even debug it using JTAG) and
every program you make is a 5-minute-work to convert from a higher AVR to a
lower one. Take a look at the ATMEGA 32, you'll have lots of fun with that.
Alexandre