arduino « Notes from a small field

Meet the team

November 3, 2009 at 22:09 | In Ones and Zeros | Leave a Comment
Tags: arduino, Blogroll, Go Clock, home automation, home easy, homecamp, hursley, IBM, mdm, mdm-workbench, scalextric, uig, User Interface Generator, user modeling, wordle

It looks 2009 is the year for people I work with to start blogging, and they’re all on Twitter… coincidence? So if you’re looking for a good read, you might like to check them out. Starting with the newest blog…

October 2009

Ed’s World (@ejellard) Off to a flying start with some great home automation with arduino, Home Easy, MQTT and a helping of hackery.

Limboworld’s blog (@jaylimburn) Conducting a scientific experiment in to the value of blogging, so make sure you get as many people to read it as possible! Some good DIY posts to kick things off. (There would have been a few DIY posts here if I’d started this blog before fitting the kitchen!)

September 2009

The World Of Gavin (@gavinwillingham) Definite technology slant with an enjoyable hint of grumpy old man which I’m definitely hoping will continue!

April 2009

Cobweb (@techcobweb)

Some really varied arduino projects in addition to home automation and tweeting cats. While the only circuit I’ve cobbled together recently is sitting in an ice cream tub in the porch, Mike is a master at packaging projects- his scalextric race timer is a work of art!

May 2006 (so blogging way longer than the rest of us!)

Nigel’s blog (@planetf1)

Not as easy to sum up given the number of posts but a distinct focus on technology of various kinds. Probably need to run it through wordle to get a better idea!

The trouble with making lists like this is that I am bound to have missed a few! I’ll just sneakily add more if I have… which reminds me, I was going to make more of an effort with a blogroll at some point soon.

Home Easy Hacking Wiki

September 3, 2009 at 12:13 | In Ones and Zeros | 3 Comments
Tags: arduino, bye bye standbye, Byron, domia lite, freeduino, home automation, home easy, Klik aan Klik uit, Klik on Klik off, PT2262 PT2272, wiki

I recently discovered that someone has created a useful looking Home Easy Hacking Wiki to pull together what information there currently is about hacking a range or related home automation hardware. Unfortunately it doesn’t yet answer Jerd’s question about the automatic protocol, so if you’ve got something working, it would be fantastic if you could add a few more details to the wiki.

Hoping to get back to finishing off a Freeduino Home Easy controller before too much longer- I didn’t even get as far as unwrapping the transmitter last time! I’m currently wondering if the Finite State Machine library that Mike used in his latest project would be useful to handle transmitting and receiving from the same controller.

If you’ve done anything like this before, any tips would be most welcome!

Update: maybe the Southampton Hack Day (via Benjie) would be a suitable opportunity to work on this. (4 Sept 2009)

Update: Thanks to Paul’s post I’ve just discovered another page documenting various 433 MHz AM signals, including devices using PT2262/PT2272 encoder/decoder chips, which klik-aan klik-uit uses apparently. (24 Sept 2009)

And there’s more:

Must get round to finishing this off myself sometime soon! Here are a couple more people who have Home Easy working with the Arduino:

(29 Oct 2009)

Impulse buy

August 23, 2009 at 18:34 | In Life, the Universe, and Everything | 2 Comments
Tags: ambient, arduino, B&Q, lamp, orb, project

I was only in B&Q to buy some paint, but spotted this on a slightly scenic route to the paint aisle…

I almost had enough will power not to buy it but it was too tempting. It’s just too perfect for some hacking; 1 arduino + 1 B&Q LED disco lamp = 3 ambient orbs I’m thinking. The back even has four screws for easy access… which I’m not going to touch until after painting the bathroom, getting married and having a honeymoon!

The IET gets sociable

April 28, 2009 at 22:05 | In Uncategorized | Leave a Comment
Tags: iet, twitter, arduino, developerWorks, homecamp, social, social networks, social networking, lotus connections, delicious

I recently read Yes, we can twitter while catching up on some E&T reading. Probably the most interesting bit for me was seeing @TheIET is also on twitter, so I tore off the bottom of the page with the link on to check out. Web 0.1 bookmarking then; I still like reading on paper.

The IET twitter account doesn’t look like it’s progressed beyond getting their brand on there; they don’t follow anyone, have a surprisingly small 168 followers and don’t seem to be talking to anyone. Still, hopefully it’s just a small beginning and, amongst the links to their web site, I did spot a press release about the launch of the new IET social networking site! That news somehow passed me by until now, so I’ve been investigating to see what it offers. To start with, I have yet another profile, which is not a big surprise. Earlier today I was scratching my head over a spiced up developerWorks profile. It has a bookmarking service which, for anyone in the IET new to such things is great. While I already use delicious for my own bookmarks, IET Discover combines bookmarks with groups, in what looks quite a similar way to Lotus Connections. There’s already a good selection of groups, although I’ve not found any that appear that active yet. Groups have always been a bit of a mystery to me in things like Facebook, never quite fulfilling their apparent potential, mostly ending up little more than a way to tag yourself as being interested in something.

Talking of tagging, from what I can tell on first look, I can tag my own profile, but other people can’t tag me, which seems like a missed opportunity. I think there’s much more value in tagging other people. In networks where you can tag yourself, I tend to have a poor attempt to start with, and then never return to keep the tags up-to-date.

And finally, I can watch people… except so far I’ve not found anyone to watch. I’m guessing it’s much like adding people to your delicious network.

Overall, it’s an interesting foray into the world of social networking. Like LinkedIn, it has a more professional focus, but it feels more limited by association with a single professional body. With recent homecamp, arduino and related projects in mind, I joined the electronic circuits group, but there are already more established social networks around those topics, whether IET members or not. Having said that, I think there is a place for more focused social networks. For example, I’m a big fan of developerWorks, where I’ve been trying to get some momentum for a community around the MDM Workbench, which is after all a pretty niche topic. So IET Discover looks interesting, and it has the potential to get me more involved in the IET. Time will tell how it turns out… maybe @TheIET will share their view…

Home Easy page on Arduino Playground

February 13, 2009 at 00:23 | In Ones and Zeros | 10 Comments
Tags: arduino, arduinoha, freeduino, home easy, homecamp, wiki

Largely thanks to @barnybug, the Home Easy Arduino hacking has been going really well. Making an LED blink is one thing, but making it blink by pressing a button the other side of the house is quite another! I’ve currently just been receiving signals, but when I’ve got the transmitter going as well, I want to do things like only relaying an on command to the socket if the current energy use isn’t too high. (Would be nice to have that working in time for Home Camp, but no promises.)

Should anyone else want to get going with some Home Easy hacking as well, I’ve created a Home Easy page on the Arduino wiki. So far it’s mostly just the sketches from Barnaby but I’m working on using interrupts instead, with the eventual aim of creating a Home Easy library for the Arduino. (There’s a Google code project for many RF protocols at once, but I just have Home Easy.)

Here’s what I have for receiving a Home Easy message with interupts so far which, with some even messier code, seems to do the trick. I would like to be able to register functions to call for specified controller/device codes, but not looked in to how that would work yet.

ISR(TIMER1_CAPT_vect) {
unsigned int pulse_width = ICR1;

if( !bit_is_set(TCCR1B ,ICES1)) { // falling edge was detected
// start over if the high pulse was out of range
if(pulse_width < min_high_width || pulse_width > max_high_width)
{
pulse_count = 0;
}
// don’t need to do anything with high pulses as long
// as they’re ok; should all be the same width
}
else { // raising edge was detected
// start over if the low pulse was out of range
if(pulse_width < min_low_width || pulse_width > max_low_width)
{
pulse_count = 0;
} else {
if(pulse_count < max_low_pulses) {
rx_wire_bits[pulse_count++] = pulse_width > bit1_low_detect ? 1 : 0;

if(pulse_count == max_low_pulses) {
message_received = receiveMsg();
pulse_count = 0;
}
}
}
}

// reset the counter
TCNT1 = 0;

// toggle bit value to trigger on the other edge
TCCR1B ^= _BV(ICES1);
}

Another Arduino Oscilloscope

February 7, 2009 at 19:41 | In Ones and Zeros | 2 Comments
Tags: arduino, freeduino, hacks, home easy, oscilloscope, PowerShell, processing, serial port

On a bit of a tangent from my Home Easy hacking, I’ve been experimenting with an alternative to the poorman’s oscilloscope. The arduino + processing hack is brilliantly simple but it wasn’t much use with the signals I was trying to look at.

Zelscope looks quite interesting but it’s a trial download, plus I wanted to keep the arduino end of the poorman’s oscilloscope hack the same if possible. The Universal Real-Time Software Oscilloscope GUI DLL Library didn’t initially look as interesting since I was hoping not to have to write any code. On closer inspection, it does have a test .exe which will import data, which only needed a tiny change to the arduino sketch from the original hack:

Serial.print( val );
Serial.print(“\t0.0000000000\t0.0000000000\n\r”);

So just get the data from the serial port, into a file and import it… either I’m missing something or getting data from a serial port on Windows is a bit of a pain. I ended up using PowerShell to do the job, starting with some instructions for reading from a serial port on the PowerShell blog. Unfortunately that doesn’t seem to work, but getting rid of the add_DataReceived line and using ReadLine() did the job:

[string]$str = $port.ReadLine()
Add-Content “C:\Temp\Data.txt” $str

I do wonder if I could use the oscilloscope GUI DLL library directly from PowerShell. I get the impression that might be possible- I expect Dale will know the answer! For now, here are the results importing a file:

Not bad, although I’ve yet to see if it makes finding the signal I want any easier. Next week I’ll be at my mum’s house trying to find an actual oscilloscope which I used to have!

Home Easy -duino

February 1, 2009 at 12:50 | In Ones and Zeros, Uncategorized | 5 Comments
Tags: home automation, arduino, home easy, freeduino, domia lite, bye bye standbye

So I’ve done a bit of playing with the Freeduino and I can see why people like Arduinos so much: they really are simple to get working. It might only start with a blinking LED but it’s nice to feel you’ve achieved something so quickly. I wish more software was like that!

The reason for getting an arduino was to experiment with some more home automation, so I’ve ordered 433MHz AM transmitter and receiver modules which look (to the untrained eye) like they should work with my Home Easy sockets. Hopefully they’ll also be simple to wire up to the arduino as well! I’ve found a couple of projects which look like they might help get me started with the code:

In fact, combining infrared with Home Easy, to turn off a couple of sockets when putting the TV on standbye for example, might be interesting. The first thing I want to try (assuming I get it working at all!) is forwarding commands via the arduino. So, for example, the arduino could relay an on command to the living room lamp, but only if the CurrentCost reading is low enough (i.e. the kitchen lights aren’t still on)!

I’ve been using the simple oscilloscope hack to do some prototyping while I wait for the AM modules to arrive, and I’ve managed to ’send’ a sample signal that looks about right. I’m not so sure about how good the timing is going to be though, and I’m still pondering about receiving Home Easy commands. Any suggestions about the best way to do this kind of thing would be most welcome!

Freeduino SB

January 26, 2009 at 22:13 | In Life, the Universe, and Everything | 5 Comments
Tags: arduino, home easy, freeduino, solarbotics, tinker it, domia lite, bye bye standbye

I recently gave in to the temptation to get an arduino. I managed to put off buying one long enough for tinker.it to run out of the useful looking starter kits so I decided go for a bit of variety and ordered a Freeduino SB instead. It arrived ahead of schedule today and it looks like a really nice part assembled kit- I dug out my soldering iron at the weekend, and I’ve got a fresh reel of solder, so I’m all set to put it together as soon as I get a chance:

Assuming it works when I’ve finished with it, and I can get an LED to flash, I’m hoping to try and get it communicating with my Home Easy sockets (getting an LED to come on using the Home Easy transmitter might be the first step).

Being a complete arduino novice, I think I’m going to need some help to get that working! My plan so far is to get a 433MHz AM transmitter and receiver module (there’s an RS Trade Counter near me) and try getting the arduino to understand the Domia Lite specification. So that’s more of a vague idea than an actual plan really! If you can help, either with what not to do when connecting an arduino to those modules, or how to program the darn thing, that’d be great- please leave a comment below!

Update: Just soldered the last few parts on the freeduino, and it blinks! (27 Jan 2009)

(I’m going to stop watching the blue flashing light any minute now…)

Update: now with spinning green thing! (28 Jan 2009)

What next? Something useful?!

Flashing light

May 17, 2008 at 20:18 | In Ones and Zeros | 1 Comment
Tags: arduino, doorbell, hacking, hacks, home, home automation

Roo’s been doing some open circuit board surgery on a doorbell so his house can twitter when it has visitors. By a stoke of luck (they were in the bargain bin when I needed one!) my doorbell flashes a light as well sounding a bell when it goes off:

Hopefully making it easy to hook up to one of these (when they’re available) with no chance of breaking the doorbell!

Bluetooth house

May 11, 2008 at 19:05 | In Life, the Universe, and Everything | Leave a Comment
Tags: arduino, bluetooth, Cityware, Johnny Lee Chung, Wii, zigbee

Since starting to dabble with home automation I’ve had a few thoughts about how bluetooth might be useful in all sorts of ways. Any early candidate for inclusion was the astounding Wiimote which, as Johnny Chung Lee has shown, is one of the most versatile pieces of consumer gadgetry ever. Waving the Wiimote about to dim the lights might be fun, and I love this use to open a door! For more immediate results though, the Wii itself seems like an ideal interface to the tiny headless server I now have running.

As Gareth’s twittering laptop shows, bluetooth is also a nice way to tell when you’re home. (Plus, it might be interesting to hook the house up with Cityware to tell you who’s at the door.) A USB bluetooth dongle could be on my shopping list soon. I’m also very tempted to go completely wild and get an Arduino (there’s bluetooth for the Arduino… and Zigbee) – watching Nicholas’ progress before I decide though.