Re: Architectures

From: Grant Edwards (
Date: 01/06/05

Date: 06 Jan 2005 15:26:21 GMT

On 2005-01-06, Paul Burke <> wrote:

>> What do people think are the comparative merits of the AVR,
>> PIC, and 8051 architectures?
>> Which one would you choose if you were teaching beginners, or
>> helping someone start from scratch?
> I'd choose something with a simple architecture and a simple
> orthogonal instruction set. I don't know the AVR,

I've used the 8051, but only studied the AVR and PIC. Of the
three, I'd say the AVR is the "best architecture" -- and there
is a gcc port, so professional-grade tools are free.

> don't like the PIC and the 8051 is a total mess (I use it a
> lot, and will consequently go to hell).

Your tense is wrong. You use the 8051 a lot, and consequently
are in hell.

> The 68000 is nice and simple,

The 68K is a very nice architecture. Not quite up to PDP-11
class, but close. Some of the 68K based SoC like the
Dragonball are pretty cool.

The 68HC12 isn't bad either, and some of the 16HC12 eval boards
are pretty cheap. [Both the 68K and the HC12 also have good
gcc ports.]

The Renesas (was Hitachi) H8 architecture is very simple and
orthogonal as well. There are both 16 bit and 32 bit versions
with all sorts of peripherals. And parts are CHEAP. You can
get a 32-bit, 25MHz processor with 128K of Flash, 4K of RAM,
two serial ports a bunch of timer/counters, etc. for $3.99 qty
1. [Good GCC port available as well.]

> the 6809 even better but both are now antediluvian and anyway
> aren't integrated like the PIC etc. (though there is a 6809
> SoC project on OpenCores). The MSP430 is fairly neat and tidy,
> but some of the peripherals are complex enough to scare most
> people off (try the FLL clock generator).

Grant Edwards                   grante             Yow!  I'm in a twist
                                  at               contest!! I'm in a
                                 bathtub! It's on Mars!! I'm
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