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...]

Nov 072012
 
How to set up a Barometric pressure sensor BMP085 on Raspberry Pi with Raspbian

Works with Raspbian hf Aug/Sept 2012 Under Pressure From previous blog posts, you’ll know I have a Raspberry Pi set up to read two temperature sensors and two light sensors (inside and outside) and log the data online at COSM Setting up temperature sensors and COSM feed But, as ever, “we want more than that!” So I thought it would be fun to add a barometric pressure sensor. Looking around, it seemed like the BMP085 was a good bet. Even better than that, Adafruit have written Python libraries for it and some setup instructions here. [...more...]

Nov 052012
 

Download Python Gertboard Programs ocol – Open Collector – Darlington Array Relay Driver I’ve managed to get the open collector ocol program written in Python. The ocol program drives the Darlington Array on the Gertboard. This can be used to switch up to 6 relays, each on a separate GPIO port. I’ve managed to write versions for both wiringpi for python (ocol-wp.py) and RPi.GPIO (ocol-rg.py) They are both included in the download link, which will always contain the most up to date versions. Here’s a comparison video of Gert’s ocol program running first, then my [...more...]

Nov 022012
 

Download Python Gertboard Programs I’ve been having a go at producing Python 2.7 versions of some of the Gertboard test suite. It’s partly as a learning experience for me and one which I hope will help others too. Which GPIO? Why not both? There’s two different ways to handle GPIO (General Purpose Input Output) in Python at the moment… Ben Croston’s RPi.GPIO Gordon Henderson’s WiringPi (Python Wrapper by Gadgetoid) The ultimate aim is to have versions of the Python programs using both systems. As a file naming convention, we’ll take the name from the original [...more...]