Category: Raspberry Pi

Link: BASIC is 50

So today (30th April, 2014)  marks the 50th anniversary of the BASIC programming language! Hurrah!

…..

To help celebrate this, I’ve made a new release of my RTB – Return To BASIC interpreter for the Raspberry Pi. RTB started life about 2.5 years ago – even before the Raspberry Pi hardware was on-sale. I wasn’t initially thinking about the Pi, just Linux in-general, but since the release of the Pi, it has gained a small and growing userbase.

Full article here:
BASIC is 50 (Gordons Projects)
Related:
Celebrating BASIC at 50 (Kresge Physical Sciences Library)

Links: The DIY home VPN experiment series

Part One: Introduction

It’s been a while since my last blog entry, and I’ve decided to catch you up on some of the projects that I’ve been working on in my home lab. This next series of posts is going to revolve around the do-it-yourself home VPN.

What is a VPN, or virtual private network?

“A VPN is a communications environment in which access is controlled to permit peer connections only within a defined community of interest, and is constructed though some form of partitioning of a common underlying communications medium, where this underlying communications medium provides services to the network on a nonexclusive basis [1].”

In essence, a VPN is private and controlled network communication over a non-private medium – the Internet.

Full articles here (source: empiric virtualization):
Introduction.
Generating a PKI (Public Key Infrastructure) for my OpenVPN.
My Virtualized OpenVPN Server.
Deploying OpenVPN using CentOS on a Raspberry Pi.

Link: How To Install & Configure BIND9 on Raspbian Wheezy

About BIND9

BIND is the most widely used DNS system on the internet, on Unix like operating systems its the de facto standard. Originally written by four graduate students at the Computer Systems Research Group at the University of California, Berkeley (UCB), the name originates as an acronym from Berkeley Internet Name Domain, reflecting the application’s use within UCB. BIND 9 was released in September 2000.

Raspbian is an unofficial port of Debian wheezy armhf with compilation settings adjusted to produce code that uses “hardware floating point”, the “hard float” ABI and will run on the Raspberry Pi.

Full article here:
How To Install & Configure BIND9 on Raspbian Wheezy (Sam Culley)

Link: Raspi EDLC UPS – A short-duration uninterruptible power supply using supercapacitors for the Raspberry Pi

For the Rundbuntplasma I wanted that the main power supply (a big 20A/5V supply) could be hard disconnected (aka operating the main power switch in our hacker space) from mains and the Raspberry will still shutdown nicely automatically. The idea is to buffer the 5V for the Raspberry using two big Supercapacitors (EDLCs) with 50F each from Nesscap. The circuit was designed to be as simple as possible, the drawback is that the capacity is not used efficiently and has only enough time for a proper short shutdown (about 30 seconds). Another drawback is that the power supply comes up slowly at startup (takes about 10 seconds before Raspberry starts booting) and also powers the Raspberry for quite a long time after the shutdown so the system must be unplugged for about 10min before it will boot up again. But there main advantage over batteries is the lifetime of supercaapacitors: They can be charged and discharged completely a few 100.000 times and are quick to charge – after ~2min they carry enough charge for proper shutdown.
So no worry of proper shutdown anymore – just unplug it or operate the main power switch and the Raspberry will detect it and shutdowns nicely while the supercapacitors provide the power for this time.

PLEASE NOTE: This article is mostly in English, but the site it is on is a German site. Therefore, the schematic diagram on the page is in a European format that may not be familiar to North American readers. However, it is simple enough that anyone that knows how to read a schematic diagram should have no problem with it. The only thing that confused us a little was the use of designations such as 1.5R and 100R on the resistors. As best we can determine, R is used in place of Ω (ohms) in Europe, but you may want to verify that with another source (and please leave a comment if we’re wrong on that point!). We are only providing a link to this article and it should be noted that we have neither built nor tested this device, therefore should you decide to build one of these, you do so at your own risk, and we will NOT be responsible for any damage or injury that may result.

Full article here:
Raspi EDLC UPS (Über Hackerspace Ffm)

Link: Remotely copy files to and from your Raspberry Pi

Most of the time I remotely log into my Raspberry Pi. Depending on what I am doing I will either SSH into it or VNC into it, which allows me to do almost whatever I would like to.

I say almost as there is a caveat.

What happens when I want to transfer a file to or from the Raspberry Pi?

I have to find a memory stick, plug it into my computer, copy the files onto it, unplug it, plug it into my Raspberry Pi, go back to my computer, copy the files over…

Then if I happen to modify a file and want to transfer it back I go through the whole process again.

What an absolute pain!

There must be a better way… Well you will be pleased to know there is!

Full article here:
Remotely copy files to and from your Raspberry Pi (Trevor Appleton)

Link: Running FreeBSD on Raspberry Pi

There are several different Linux based distributions available for the Raspberry Pi, including Raspbian, Arch Linux and Fedora. However Linux isn’t the only operating system that can run on the board. Among others, including RISC OS, is the popular Unix-like operating system FreeBSD.

FreeBSD has a deep heritage and is in fact derived from the Berkeley Software Distribution (BSD, sometimes called Berkeley Unix) a version of Unix produced by the University of California, Berkeley. For copyright reasons, FreeBSD isn’t allowed to call itself Unix, however; it is actually more Unix-like than Linux. For those who are interested in running FreeBSD on Raspberry Pi, here are the installation instructions.

Full article here:
Running FreeBSD on Raspberry Pi (Make Tech Easier)

Link: Pelican: A fast blog/CMS for the Raspberry Pi

… I wanted blogging software to run on the Raspberry PI which was:

  • Served at a reasonable speed.
  • Easy to write.
  • Easy to maintain.
  • Portable to other platforms, should I choose to move to another server.

After looking high and low for a solution, I finally came across my answer: Pelican.

Full article here:
Pelican: A fast blog/CMS for the Raspberry Pi (874.org.uk)

LInk: A Raspberry Pi Fridge/Freezer Temperature Monitor and Alarm Project

I’ve been blogging about my experience in Road Test reviewing the Ultimate Raspberry Pi Bundle. As a part of this Road Test I’m creating a Fridge/Freezer Temperature Alarm system for our local food shelf, Channel 1. You can see where this Road Test started for me here
In this post I’ll bring together all the steps required to build your own Raspberry Pi powered temperature monitor project.

Full article here:
The Complete Channel One Temperature Monitor and Alarm Project – The Ultimate Raspberry Pi Bundle (element14 Community)

Link: Finding Your Raspberry Pi’s System Information

The Raspberry Pi has a lot of system information available like details about the CPU, the current temperature of the processor, the amount of memory and so on. Not all of the information is available in one place; however, if you know where to look, you can discover quite a lot of interesting data about your Pi.

Full article here:
Finding Your Raspberry Pi’s System Information (Make Tech Easier)
Related:
How to Overclock Your Raspberry Pi (Make Tech Easier)

Link: Setting up Prosody (XMPP server) on the Raspberry Pi for house/apartment/secret club house-wide chatroom

Figure A

Although I only live with 4 others, wife, son & 2 cats, in a small 5 room apartment most evenings we are in different rooms, or in the summer 3 different floors, wearing headphones chilling to our own choices in music & tv. As I think it’s uncouth to yell out of the window or across the apartment to get someone’s attention I setup a Raspberry Pi Model B as an XMPP server running MUC. As it’s only for 3 people, unless we have visitors, I chose to run Prosody, it’s pretty lightweight, easy to setup, the stable version is in the raspbian repos & i’ve used it before. I’ve also used and run ejabberd, openfire, tigase, jabberd,… but IMHO they are heavier on resources and a bit harder to setup, and are overkill for my needs and anyway I like lua.

Full article here:
Setting up Prosody on the Raspberry Pi for house/apartment/secret club house-wide chatroom (Executing Gummiworms)
NOTE: The author appears to have taken down the above article, but there is a cached version at the Wayback Machine.
Related articles:
Using the prosody xmpp/chat server (Debian Administration)
Installing Prosody XMPP Server on Ubuntu 12.04 (Precise Pangolin) (Linode Library)