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…]

Oct 182012
 
Getting an inexpensive 16x2 LCD screen working on the raspberry pi

I finally freed up one of my breadboards. I got my semi-permanent temperature sensing interface fully up and running with the Pi Cobbler – logging to COSM. So now I could take the components off my other breadboard and free up the Gertboard for other experiments. LCD Next The next thing I wanted to get working was a 16 x 2 LCD panel. (£6 from Tandy) Having seen other people get these working, I figured it couldn’t be all that hard and it wasn’t too bad actually. But I did make one small mistake along […more…]

Oct 152012
 
How to fix a broken SD card slot on your raspberry pi

You would Pi too if it happened to you :( Just as I was finishing up my last blog post, the review of Adafruit Pi Cobbler, my foot snagged on a network cable and hoiked my Pi onto the floor. It landed on the SD card and the feeble card slot took no prisoners. The card slot broke as it was predestined to do, the moment anyone looked at it harshly or in the wrong tone of voice. This Pi, my friend since 15th May 2012, is accustomed to living in a beautiful Yoctopuce case, […more…]

Oct 122012
 
Adafruit Pi Cobbler Review

Most of my recent posts have been focussed around the Gertboard. Not surprisingly, since not many are out there yet. Now that Farnell Element 14 has started shipping (I got mine today), we should expect to see a proliferation of info about clever things people have done with theirs. One thing Gertboard has done for me though, is kindled an interest in interfacing. Previously I posted about temperature sensors and logging. Since developing the temperature data logging capability, I now want to keep that going, but still be able to mess around with the Gertboard. […more…]

Sep 212012
 

Now I’ve got my Gertboard assembled, I thought I’d run some of the programs Gert supplied for testing and learning. First up LEDs. Delighted to say it worked a treat, so i thought I’d bring you a world premiere of the first blogged video of a Gertboard (sold to the public) in action. LEDs, camera, action… …and cut. Short and sweet. In case you’re wondering, I didn’t have enough jumpers and straps to make use of the last two LEDs on the board. I’ll be putting the rest of the board through its paces soon.