Toys for the Boys - for Christmas!

[KenB]

Nice to have yet another thread hijacked by mindless drivel.

Ken


EDIT: Off topic messages removed.

[Paulh_Boats]

Not sure I'd choose arduino for data logging, lack of proper storage could be a barrier.  Would prefer something higher powered like a gumstix pc: www.gumstix.com  ... but they are a bit pricey. How about an old netbook pc from ebay?  Think you can pickup the first gen Eee's for under a 100 quid. 

Can't find the link but I saw a plug-in SDCard pcb for the Arduino for about 15 squid. That will give oodles of non-volatile storage.

[KenB]

Paul,

The SD shield was featured on Stephend's  Libelium site here:

http://www.libelium.com/tienda/catalog/product_info.php?products_id=66&osCsid=ca4ea255ea83d3ed1352ff0f100818cb

18 Euros


Ken

[cornishben]

... Think you can pickup the first gen Eee's for under a 100 quid. 

Guess I'm reinventing the wheel here. I have an eeePC which could be put to good use monitoring (its currently used as an expensive mp3 player!), as it has storage + ethernet already.  This is fine for the currentcost meter monitoring as this has a serial output to USB, but I guess the eeePC isn't so easy to interface to for monitoring temperature probes, etc.

Need to look up its power consumption as well. Doesn't strike me as being so hackable, although running linux i guess it is if you know what you're doing (not me!)

[Paulh_Boats]

Soon I'll add a poll for the popular Arduino projects, then maybe we can collaborate a bit?

[KenB]

Paul, Ben,

If you purchase the "official" Arduino ethernet Shield, it come with a SD card socket fitted.  It uses the Wiznet chip to provide IP access, and this chip holds the TCP/IP stack.  This frees up a lot of resources on the Arduino - which with only 1k of RAM is not the most powerful of platforms.

I however bought the nuelectronics ethernet shield based on the Microchip 28J60 ethernet controller, and the Arduino running a very much cut down TCP/IP stack, so I will have to be contented with a less capable design. 

I am however fascinated with minimalist internet hardware and if you only want to serve a few temperature or logger readings to the net, then it should be possible with a simple mcu and ethernet chip in a design that is not going to cost the earth.

My philosopy is to start with something simple that I can understand, and then work from there - rather than diving in at the deep-end, and failing to grasp the fundamentals because they are obscured in thousands of lines of someone else's clever code.  (This was the problem I had with the PIC based internet dev board).

My approach will be to interface the Arduino to my 2 channel digital thermometer, which spits out a pair of indoors and outdoors temperature readings every second on a serial interface. The Arduino will grab these, average them over say a minute and then serve them to the net.  I can then use the Pachube service to log and graph them.  Once I've achieved the basics of serving a changing physical parameter to the net, I can then look at pulse counters for electricity meters and the like.

The Arduino is a fairly minimal platform, and there are moves afoot withing the community to make a more "resource - full" design based on one of the bigger ATmega chips - providing more codespace, more RAM and more I/O pins. However, it will be interesting to see what can be achieved first with the basic board - and see whether it suits the application of renewables monitor and logger.

It still hasn't arrived - god I hate the Christmas Post!!



Ken

[Paulh_Boats]

Ken,

Thanks for the info. I like the Wiznet solution has it wraps up the complex and messy TCP and IP protocols in the hardware and works with the official Arduino ethernet library.

Anyways, I have started a poll in the Home Automation forum to guage the popular topics. As I said before you have found the ideal platform for small scale renewable automation..... should we call it micro-automation?

cheers
Paul

[renewablejohn]

See my avatar for my christmas present. A proper toy for the boys

[cornishben]

Ken - I guess judging but your other post that your delivery arrived!

I've also ordered the nuelectronics freeduino/ethernet shield, note here yet..  but i'm hoping it'll be sufficient to average a couple of temperature readings + flow values and serve them to the net (as you say), I can then expand software around this to calculate heat output and work from there. Defiantely best to start with some LED flashing and the like with jsut a few lines of code. I take it the uk 'freeduino' doesn't have an SD card interface then?

[KenB]

Hi Ben,

The Freeduino turned up shortly after I moaned about the Christmas post delays!

I managed to get all of the nuelectronics example code to work

Downloaded from here

http://www.nuelectronics.com/estore/?p=14

I then ran into problems because one of my laptops kept crashing when I tried to upload the compiled code to the Freeduino board. After this happened twice I resorted to using my Toshiba notebook - which worked fine.

I made some changes to the webserver example so that it would read a thermistor rather than the Dallas temp sensor.

This worked OK as a local server, but I have yet to remember how to make my router look transparent to incoming requests.

I then tried the example code on the Pachube site, and found that this refused to compile unless I commented out the <#include stdio.h>   line in the ethershield module.

Hopefully tomorrow I will have a transparent hole through my router so others can see the Arduino server.

The Nuelectronics ethernet shield is completely different form the Arduino version - its basically just a Microchip 28J60 ethernet controller and it relies on a cut-down TCP/IP stack running on the Arduino.

There is no SD card socket - but I have downloaded the SD library and this should be relatively simple to bodge on.


ColdPlay: "Nobody said it was easy..."


regards,



Ken

[Paulh_Boats]

I've ordered an Arduino but not the Ethernet shield... I don't think a rainwater pump controller needs to be on the Internet.  ...or does it? 

[wyleu]

If I had my way every light bulb would have a V6 ip address.