Comments on: Hacking the doorbell

By: Grant Gibson

Grant Gibson — Mon, 30 Mar 2009 13:30:05 +0000

I’ve recently built one of these for my Windows server at home. Found your site when looking for suitable code to run on the Arduino — thanks for that!

@Patrick – I had to write some Perl code to listen to the incoming serial stream and do something based on that data. My write up and Windows-compatible Perl code is here if you’re interested…

http://www.grantgibson.co.uk/blog/index.php/2009/03/29/putting-doorbell-online/

Grant

By: Shinykatie

Shinykatie — Wed, 14 Jan 2009 09:49:14 +0000

Was just googling for wireless doorbells and your blog came up. The internet is a tiny place I tell yer! Nice geekout, well done.

x
Katie

By: Roo

Roo — Sun, 04 Jan 2009 10:05:48 +0000

Yep, that's right. The Arduino is good at interfacing with hardware, but when I want to use an input to do something webby I had to read the serial line and handle the event on a computer. A nice alternative, if you want to avoid having a computer running the whole time, might be to use an Ethernet shield which plugs into your Arduino like this one from Nuelectronics or this (announced but unreleased) one from Tinker. I have not played with an Arduino Ethernet shield yet. From what little I know about the Ethernet shields, I'd imagine that using one to send an email should be pretty straightforward. I've been jealously watching Nick's experiences with a pre-release one from Tinker. He gave a great presentation at HomeCamp which is well worth watching.

By: Patrick

Patrick — Sun, 04 Jan 2009 00:40:29 +0000

So, do you have a separate app on your Mac that reads the serial data from the Arduino when the button is pressed?

It doesn’t look like the Arduino language has much to it, unless you extend it with your own C/C++ code.

My idea was to have some application on the PC listening to the Arduino COM port for any data that it sends, and then handle the “ring” accordingly. In my case, I don’t want to POST anything anywhere, just send an e-mail from the local machine.

By: Roo

Roo — Sun, 04 Jan 2009 00:12:41 +0000

curl is a tool for talking to web servers. In this case (via the -d option) it's being used to make an HTTP POST. The computer I was using as a bridge from the Arduino to the web is a Mac, which has curl ready to go on the command line. If you're using any sort of Linux, it should Just Work, otherwise you'll want to find a copy of Curl or handle the HTTP POST in whatever way is most comfortable for you.

By: Patrick

Patrick — Sat, 03 Jan 2009 13:47:36 +0000

Hi there – I stumbled across this article and became very excited… exactly what I’ve been looking for.

I’m still trying to figure out how the code “sketches” work… but have a solid background in C/C++, C#, Java, so should be no problem.

However, when the device receives the serial data from the push button, how are you calling your other script that sends the e-mail? It’s this command:

“curl -u email@example.com:password -d status=”There’s somebody at the door” http://twitter.com/statuses/update.xml”

Where is the file “curl” located and how do you call that from the code on your controller device?

Thanks!

By: roo

roo — Thu, 11 Sep 2008 15:52:58 +0000

But if I’m out, how am else am I supposed to know if someone has rung the doorbell unless it’s being logged on the internet?

By: Martini

Martini — Thu, 11 Sep 2008 15:27:07 +0000

I’ve been reading all this stuff, and I have to say it – hand on heart. You people really should get out more.

By: jb

jb — Fri, 22 Aug 2008 08:14:12 +0000

Let me compare that to my setup :-)
When someone rings the doorbell and i’m not at home a popup on my PC opens and shows the person at the door (when the PC is online). Otherwise I get an email with the photos. The doorcom calls my mobile phone and I can talk to that person. Of course I can open the door remotely… Or the garage when a mailmal wants to leave a parcel…

By: Wim L

Wim L — Thu, 21 Aug 2008 20:34:40 +0000

Knock-detectors: do-it-yourself and commercial.