[time-nuts] I want a good micro-controller
hmurray at megapathdsl.net
Wed Aug 13 14:50:53 EDT 2008
> It needs to drive a display of some form (standard LCD is fine but
> other options would be good) and since nearly all my references are
> based on 10MHz it would be nice if it could be clocked at that speed.
> I used to program the Acorn Achimedes and so ARM would be nice and
> since I'm a 20 year experienced C programmer (not C++) then that is
> what I'd like to program it in.
> Thoughts, ideas, comments would be appreciated!
Are you looking for a chip to use in a board you are going to design, or an
existing board that will do your job, possibly with some hacking?
I'm not up to date on boards. The mega-donkey looks like a good straw man.
(I think you need something else to program it.)
Vendors often have inexpensive low end development kits. (Some of the high
end boards are quite pricey for a hobby project.) Here is a sample:
(It needs a programmer too.)
Have you considered using a laptop? Older (real old?) ones had printer ports
so you could get a PPS in.
Assuming you are looking for a chip:
I know of 3 families of 8 bit chips: AVR from Atmel, PIC from Microchip, and
8051s from several vendors. It's a cut-throat market area. I think they all
make chips that are roughly equivalent.
If you need something more powerful, the ARM chips are probably the way to go.
I like the Atmel chips, both ARM and AVR. Their I/O units are generally not
too quirky and the documentation is pretty good. Digikey carries them.
They usually have a one page sheet that compares all of their chips. Here is
a sample, but it doesn't show the I/O stuff.
> Oh and cheap!
I don't think the price of the CPU chip will be a big deal for a low volume
project. Things get interesting if you want to buy a million of them.
Often, a vendor will make several versions of a chip with the same I/O but
different sizes of RAM/Flash. For a hobby project, I'd get the biggest one,
just in case.
Odds and ends:
If you have a PPS, you probably have 10 MHz too. If you can use that for
your CPU clock, then you don't have to worry about calibration.
Running off batteries won't be a problem. All your power will go into the
backlight for the LCD. :)
These are my opinions, not necessarily my employer's. I hate spam.
More information about the time-nuts