On Tue, Jan 24, 2006 at 07:42:56PM -0800, Shawn Wilton wrote:
> Don't forget about the FREE GCC AVR C compiler.
> 
> (You never mention what previous level of knowledge, if any, you prefer your
> students to have.)
> 
> 
> On 1/24/06, Russell McMahon <apptech@paradise.net.nz> wrote:
> >
> > > I'm thinking about putting together a community ed
> > > class for the spring "semester" here in Minneapolis,
> > > and I'm wondering what everyone's thoughts are on
> > > the most cost effective method is to get my students
> > > set up with a programming/prototyping board that they
> > > could make good use of would be.
> >
> > If you are happy to stray from the fold then a close to zero cost
> > solution with vast utility can be achieved.

There's actually no need to stray from the PIC world in order to gain
this utility.

> >
> > The most basic AVR programmers operate from a parallel port (for those
> > who remember what that is) and typically a 74HC244 IC and a few parts.

Same for the PIC if an low voltage configuration is used. Even for high voltage
it's only a smidge more.

> > A typical circuit copyright Olimex 2002 can be found at
> > http://others.servebeer.com/temp/avrprog.jpg and, I imagine, on
> > Olimex's site.

My Trivial Low Voltage Programmer is about the same:

http://www.finitesite.com/d3jsys

I use a 74HCT573 for level shifting and because I like the part's pinout.

The page also points to the high voltage and ICSP capable versions.

One of my users finally solved the long cable issue. He found that grounding
the shield through a small value cap allows for cables over 10 feet to work
perfectly.

> Google will tell you about many others. So far material
> > cost is scrap or under $10. Using a(n Olimex?) PCB may be a good idea
> > but the keen could do it on vero/vector/... board.

Agreed. In fact even a breadboard can work for such a simple configuration.

Your bootloader idea I find to be a good one two. The one two punch of a
simple programmer plus a bootloader can simplify development issues for
novice and intermediate users.

> > Power supply costs as little as you wish with all the usual tricks.

I generally pull power from the PC. While shorting issues are possible, it's
cheap and effective.

> >
> > The AVR is now running.
> >
> > Free essentially unknobbled BASIC (apart from a code size limit which
> > is reasonable) can be had from BASCOM.
> > Atmel's IDE is also free.
> >
> > While compelling people to do hello world / blinking LED etc in
> > assembler, doing it in BASIC, feelings of horror notwithstanding, is
> > liable to get a lot more people going a lot quicker, he a lot more
> > done and interest more people. With BASIC you can progress from
> > blinking LED to Christmas Tree light controller (may The Lord have
> > mercy ...) in an evening.

For pics JAL may also be a possibility.

> >
> > Add up cables, power etc and you get: Programmer, BASIC, IDE, ... all
> > for, with a little care, maybe $20.
> >
> > Maybe you can do the same with PIC, but the point is that people can
> > and do with AVRs.

Both are capable platforms.

BAJ
-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist