Posted by Steve D on July 2, 2009, 4:13 am
I'm not selling... just sharing...
I remember a thread on this newsgroup several months ago about controllers
for solar systems.
I've recently discovered the "Arduino Duemilanove". It's described as: "...
an open-source electronics prototyping platform based on flexible, easy to
use hardware and software".
I bought one of these off of ebay that came with a USB cable (for
programming) for about $5 (including shipping).
It's a little 8 bit microprocessor board that has:
14 digital I/O
6 analog inputs
32K program memory
2K static memory
Supports I2C and TWI (1-Wire)
The development environment is free and you can find it from the link
The board can be powered from the USB or a 9V supply. I plan to use the USB
for development and the 9V supply once I get something running.
The coolest thing is that once I got up the nerve to hook the thing up and
try flashing LED's, it took all of about 2 mintues to get it working.
Most of what the board does is let you harness the Atmega microcontroller.
I'm mostly into software, so I didn't want to make my own board. The
software they provide is pretty simple, and I have found easy to use.
While I haven't tried the TWI, but have found temperature sensors on eBay
that are supposed to be with 1/2 degree C. The DS10B20, you can get 5 for
$4 on eBay (I haven't found them cheaper anywhere else) looks like it would
be ideal. You can hang multiple sensors off of 2 wires.
There is another board based on the Arduino called the Seeeduino that uses
all surface mount components and looks like it would be suitable for a
production component. I picked the one with the socketed microcontroller so
I can just replace the chip if I blow it up (I'm kind of a rookie at this).
I'm toying with the idea of using this controller to run pumps for a solar
hot water system.
Posted by PCPaul on July 2, 2009, 7:22 pm
On Wed, 01 Jul 2009 21:13:20 -0700, Steve D wrote:
I've been looking at them too. You can get various daughterboards (called
'shields' for some reason) with various capabilities. LCDs are one use,
the one I'm particularly interested in gives you lots of different motor
drive circuits (the standard board only has very low power switching).
You get DC motor, stepper motor, RC servo drivers and more all on one
board, complete with an easy software library to drive them all from.
Well worth a play. I can also confirm the simplicity of programming them
- my 8yo son was doing his own 'Knight Rider lights' (using timed fading
LEDs) with minimal guidance after only about 20 minutes..
Posted by Martin Riddle on July 2, 2009, 10:52 pm
Are they using the GNU compiler? I have a STK500 with a mega8 laying
around here, and recall using the GNU C compiler.
Posted by PCPaul on July 3, 2009, 4:55 pm
On Thu, 02 Jul 2009 18:52:23 -0400, Martin Riddle wrote:
Well.. yes and no. It does use avr-gcc and the rest of the GNU embedded
toolset (amongst many other libraries), but you wouldn't know it to use
That's one of the things that has helped it get so popular - there's a
pretty complete IDE available wich you program in a very simple subset of
C/C++. The IDE also handles all the 'tricky' stuff like cross compiling,
uploading to the board, running startup code, event processing loops,
interrupts etc etc.
It really is simple to get going with it. And even after years of
programming and electronics it's still weird to start a program off
flashing lights, driving motors etc. then detach it from the PC
completely and have it still do it's stuff.
http://www.arduino.cc is the main site, with all the software downloads