Feb 052013
 
Raspberry Pi Model A first impressions and photos

I was keeping an eye on the RS and Farnell sites on Monday morning because I’d heard a ‘reliable whisper’ that the model A was launching this week. I didn’t know what day, but I figured it might be Monday. No sign of anything early morning, but then I forgot and didn’t see Liz’s announcement on the Pi blog until a couple of hours after they went live. By that time, RS was showing back order, but Farnell had stock levels of ~1800, so I snagged one. I got a “shipped” email about 3 hours […more…]

Feb 032013
 
HDMI to VGA converter part 2 - VGA projector

This is part 2 of my review of the HDMI/VGA 1080 Ultimate HD Video Converter. It covers comparison of VGA and HDMI in the GUI; use of an old 1024 x 768 VGA monitor with the Pi; using a VGA projector to show a video; trying out an MHL adaptor with a phone and VGA monitor. If you haven’t seen part one yet, you can find that here. To complete the review, I set myself the following tasks… see if I can get it to go full-screen in GUI by tweaking settings do some side […more…]

Jan 152013
 
Emulators galore on one raspbian image

Carles Oriol has put together a raspbian image with just about every emulator you can imagine, including… ZX spectrum DOS / Windows 3.1 Commodore 64 Apple ][ Oric 1 Atari 2600 ScummVM Arcade (MAME, I think) The only one of note that I didn’t see was BBC Micro. I don’t know if it’s available for the Pi. (But there is RISCOS, of course) It’s a very impressive piece of work. No details yet if he intends to republish. It’s possible there may be some copyright issues if he does. For the moment, though, there is […more…]

Jan 112013
 
HDMI to VGA Video Converter with sound for Raspberry Pi - Review

One of the compromises that had to be made in designing the Raspberry Pi to be so small and so cheap was the decision to exclude a VGA connection. The BCM system on a chip already has HDMI and composite onboard. Adding VGA capability would have needed additional hardware in the form of a VGA chip and a VGA port. VGA ports are quite chunky too. Adding one would take up as much “edge space” on the board as both HDMI and composite ports together. Have a look at this photo… I took this VGA […more…]

Dec 212012
 
The Self-resetting Raspberry Pi

Recipe for auto-reset Pi. Take one Rev 2 Raspberry Pi, a few carefully selected slices of fresh Python, one GPIO port (’25 vintage, preferably), one relay (a twin pack is OK, but not AA), one Darlington array (leave the spikes on), a sprinkling of mixed wires and arrange it all carefully with a breadboard. It should end up looking something like this… I decided to take the P6 reset header one step sillier further. Just for fun. ;) The idea here is to use one of the Pi’s own GPIO ports to switch a relay […more…]

Dec 142012
 
Using a Darlington Array as an inverter for reverse polarity RGB leds

RGB LED RIP :( Last week, I was wiring up a demo with a three colour RGB LED, and accidentally wired the pin for the red component straight to 3V3 (plugged it into the wrong port). It went “crackle” and then turned black. Ooops. Now it’s a GB LED, the red’s a gonner. :( “Dammit. I wanted to shoot a video with the Quick2Wire Interface running the RGB LED. It’s 7pm and if I order some they won’t be here for two days.” “Oh I know. I’ve got an RGB LED in an old Christmas […more…]

Dec 082012
 
Plan 9 operating system for the Raspberry Pi - demonstration by Richard Miller

There’s not much I can say about this except that it’s tremendously impressive – if you’re a bit of a geek (like me). If you think computers are all about fancy-pants graphics and visual effects, this one might not be for you. ;) Richard Miller demonstrated his recently finished Raspberry Pi port of the Plan 9 operating system at the Oxford Raspberry Jam in November 2012. I caught most of it on film. Plan 9 is a very lightweight and powerful operating system that is written for software developers. I find it very impressive indeed. […more…]

Nov 302012
 
Review of ModMyPi case for the Raspberry Pi

I was looking for a Rev 2 Pi, as I wanted one to see if the revision checker function of the Python Gertboard programs worked properly. Farnell was quoting up to 3 weeks lead time, RS are out of stock. :-( Nobody else seemed to have it in stock, but over at ModMyPi, they said they would have some in within a few days. Sold to the man in a hurry :-P It turned out that it was with me within 48 hours, which was excellent. If you buy a Raspberry Pi from ModMyPi you […more…]

Nov 232012
 
Pi controlled light and fan from mains power socket

Don’t try this unless you know what you are doing. Mains electricity can kill you. Update Since publishing this blog post, I’ve had some feedback about the way I’ve done this and it needs improvements and a redesign to make it safer. Please don’t copy this. I’ve removed some photos so I’m not setting a bad example. Back to the original post Ever since getting my Gertboard in late September, I’ve been thinking about using a Raspberry Pi to switch “proper things”. By “proper things” I mean real, useful, BIG things using mains electricity. :eek: […more…]

Nov 132012
 
Temperatures, light levels, pressure, logging, LCD, PCB - bringing it all together

Ever since getting the LCD working and temperature and light level logging using COSM and the Pi Cobbler, I’ve wanted to compact all of this onto a single add-on board. I’ve mentioned this in forum posts and other blog articles, but a part of me thought it wouldn’t happen. It took me a few weeks to bring it all together, but it’s finally done and it works :) The circuit I don’t have a full circuit diagram. I may try to put one together later. :) It’s a bit messy but I’ll try to describe […more…]