[sdiy] LED matrix - was: PIC / Atmel Programmers

[Bert Schiettecatte]

hi Neil,

I tried the parallel programmer too, and I just don't like it. Besides,
it's easy to blow up a parallel port on a laptop. I've used AVRGCC and 
I'm pretty happy with it actually. 

A totally other question : I'm not an expert on CMOS/TTL IC's, I'd like 
to use a couple of 4051's to interface a big 32x32 discrete LED matrix 
to my AVR. Is this possible? Does anyone have a more efficient way of 
doing this interfacing? I'd like brightness control over each LED 
(through PWM...?).

thanks,
bert

-----Original Message-----
From: Neil Johnson [mailto:nej22 at hermes.cam.ac.uk]
Sent: dinsdag 27 mei 2003 23:58
To: Bert Schiettecatte
Cc: synth-diy at dropmix.xs4all.nl
Subject: RE: [sdiy] PIC / Atmel Programmers


Bert,

> Why did I do this? Because almost all serial programmers on the net
> use some weird RS-232 hack that doesn't work with my laptop. The key is

Did you try the parallel-port programmers?  They don't need any level
conversions at all, only a buffer to drive the long programming cable and
drive the programming pins on the AVR.

I use a simple parallel port programmer from an old STK300 kit.  There are
plenty of circuits on the net.  For example:

	http://www.iready.org/projects/uinternet/ispdongle.pdf

This works with AVRDUDE, included in the AVRGCC package you can download,
for free (you did know about the free Gnu C/C++ compiler for AVR?), from:

	http://sourceforge.net/projects/winavr

There's lots more information here:

	http://www.avrfreaks.net/

Hope this helps,
Neil

--
Neil Johnson :: Computer Laboratory :: University of Cambridge ::
http://www.njohnson.co.uk          http://www.cl.cam.ac.uk/~nej22
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