Home automation using open source

Introduction

A friend got me into the whole home automation stuff when he told me he wants to control his heating from everywhere in the world. And he did. I used to have a similar system which allowed me to control the heating of the whole apartment from my living room. But this is going much further. He, and now me as well, is using FHEM. This interfaces multiple systems from a single UI. Quite neat.

FHEM

The server itself is written in Perl. FHEM stand for „Freundliche Hausautomation und Energie Messung“ which means „Friendly Homeautomation and Engery Measurement“. There is also quite a large community supporting this project so I thought it is worth a try. By now I don’t have very many devices connected but there is definitely going to be more.

I myself have installed FHEM on an AVM FritzBox 7490 which is my router and turned on all the time anyways. Therefore it does not waste any extra energy.

Connecting the washing machine

My major problem is, that my washing machine is in the basement. This is 5 levels below. I hate going down to see that it is still running. This is the main point for introducing the FHEM server. As there is a huge distance from our apartment to the machine, I had to find a way to communicate. The easiest way was using power line. Using power line ethernet I could connect the washing machine to my home network. From there on it was easy to find out the state of the machine. I just had to find a way to measure the power consumption. Fortunately there is a „all in one“ adapter that can handle this. Just take a look at the AVM 546E adapter which can do both, measuring power (and current), switching the device as well as acting as a power line connector.

With this my machine was in my network. The next step was notifying us when the machine was ready. I know, this is an advanced topic in FHEM but I suggest reading the command reference first. After that you should know a lot about the capabilities of FHEM.

Summary

I know this does not really answer your questions. The next post will go in way more detail to show how this is accomplished. This is just rather an introduction.

KLP / KK Android

Android

Who knows me know that I love Android.

This is going to be a short post. I hate the fact that Google is going to call the (at THIS moment) new OS K*tK*t. I will not write the whole name due to search eninge reasons which I don’t want to support.

Well, Google starts to annoy me. After turning off Latitude, this is the next step to make deals like this. Stick to what you were praising.

 

P.S. a 5.0 would have been nicer. BTW, what happens after Z?

Android LeeDroid and Facebook App or FriendStream not working

AndroidPrerequisites

You are using LeeDroid on your HTC Desire and Facebook stopped working. This affects the native app and also FriendStream by HTC. Within the native app you can still update the stream but cannot read any messages. If you delete your native user account and readd it, it will give you an exception like this

( org.bouncycastle.jce.exception.
ExtCertPathValidatorException: IssuerName(OU=Class 3 Public Primary Certification Authority, O="VeriSign, Inc.", CPS Incorp.by Ref. LIABILITY LTD.(c)97 VeriSign, OU=VeriSign International Server CA - Class 3, OU="VeriSign, Inc.", O=VeriSign Trust Network) of signing certificate. [javax.net.ssl.SSLHandshakeException])

Within HTC FriendStream it will give you a „service unavailable“ error.

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Turn off shutdown event tracker in Windows 2003 32bit

Even though it’s old, I still like it. The only thing that bothers me about Windows 2003 Server is that annoying shut down event tracking. There are multiple articles about how to use the group policy editor in order to turn it off. In some installations this is not an option as the system folder in the administrative templates is not available.

You can still turn it off via a registry entry. You simply add a new DWORD entry here: HKEY_LOCAL_MACHINE\\SOFTWARE\\Policies\\Microsoft\\Windows NT\\Reliability

With the new DWORD value: ShutdownReasonOn (0 = disable; 1 = enable)

Secure connections via Android and DD-WRT from everywhere in the world

Introduction

You want to have a secure connection from your handset to the internet, even when surfing while using an unsecure wireless connection or an untrusted network? This can be done quite easily in case you meet the following preconditions:

  • Your handset is running Android 2.1 or higher
  • It is rooted
  • You own a router that is running an OpenSSH server (this article is using DD-WRT)
  • You have some dynamic IP service to connect to your home router (e. g. Dyn.com)

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WebChannel 7 for SAP ERP: Setting up an NWDI track in NW 7.3

Introduction

Setting up a track in NetWeaver 7.0 is well documented. You can find it in in Service Marketplace at the CRM installation guides. It is a different story for NetWeaver 7.3. As support for NW 7 is running out, it might be a good idea to set up new projects in a NW 7.3 environment. Therefore we will go through a setup of a track in NW 7.3 and how to connect the track to a run-time system. In this case we will just the NWDI as run-time system. This is not recommended in a live environment. But hey, it’s a sandbox to play with. This tutorial is for people with experience with SAP software and especially the WebChannel application. We will only go through the ERP part. CRM is working accordingly, you just need more SCAs. Please keep this in mind.

(Updated 04.05.2012)
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Influence the flashing of your laptop’s WiFi LED

The Problem

You have a brand new laptop or wifi card. The little LED that indicates the wifi status behaves differently from what you expect. Either you want it to flash when it’s transmitting data or you dislike the flashing and want it to just light up and stay on. Read on to see what you can do.

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Encrypted backups in „the cloud“

The Problem

Backups are important. There is no doubt about this. If you have ever los data due to a harddisk failure or malware, you will most probably agree. But where should you store you backups? I used to have two strategies.

  • I have two identical HDD’s. One for working with, one just for backups
  • The media server (this one) below my TV set also has a copy of the backup but not as current

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