Posts

PCB antenna design
One of the circuit boards I’m developing would benefit from an onboard antenna, so I started hunting for design tips. The following three PDF documents do a great job of explaining the basics:
David Cannings
Dec 20, 2010 1 min read Electronics
Welcome to the IPv6 world

This blog can now be reached over IPv6 (or ipv6.edeca.net), which is surely the final nail in the coffin of IPv4 across the internet.

David Cannings
Nov 7, 2010 1 min read Computing
PCB0002 - LED matrix
It has been ages since I have updated this site. I have started to document some of the PCBs I have created The first is an 8x8 LED matrix, with code for some whizzy effects.
David Cannings
Oct 30, 2010 1 min read Electronics
Project
O2 iPhone (iOS4) provisioning bug
I finally upgraded my old iPhone 3GS to iOS4, but it wasn’t a smooth process. It seems O2 have a problem with their provisioning process because, after the upgrade, all of the carrier settings had disappeared.
David Cannings
Jul 10, 2010 2 min read General
Net::LibNIDS 0.1 released

The other day I pushed a new version of Net::LibNIDS to CPAN. It interfaces with the C library libnids in order to provide TCP stream reassembly and returns the data to your Perl callback.

David Cannings
Jun 30, 2010 1 min read Computing
Production music samples
Whilst looking for some music to use as jingles/beds for a charity radio project I assist I found FreeNotesMusic. From a quick listen there are some fantastic tracks, really nice composition and production.
David Cannings
Jun 6, 2010 1 min read General
Better than grep
Anybody who has used command-line systems for a serious amount of time will love grep. But today I stumbled across ack, which (for many things) is better than grep and a whole lot nicer to use.
David Cannings
May 29, 2010 1 min read Computing
Cooking with gas, my first SMD board

My first bunch of boards arrived back from BatchPCB and I’m really impressed.  Great printing for the silkscreen and a really professional looking product.  One of the boards I ordered was a breakout board for the SMD PIC 18F2321, the first surface mount board I have tried.
David Cannings
May 10, 2010 3 min read Electronics
I am not a photographer

During a recent conversation with another Dave he pointed me at the Facebook group “No, you’re not a photographer, you just own a camera” (update May 2011: this no longer exists).

Whilst I don’t agree with most of the comments on there (they are generally rude and unhelpful) it does raise an interesting point: How high the bar should be set for whether you are really a photographer or not?

David Cannings
May 7, 2010 3 min read Photography
Limiting command runtime in Linux
It is sometimes useful to limit the running time of a process, either to stop it from using up all resources or to make sure nightly cron jobs don’t continue into working hours.
David Cannings
May 2, 2010 1 min read Computing