1202 ALARM

Thanks to the work of some guys on the RaspberryPi forum, Gambas3 is now running on the little computer.  So after a couple of hours work installing a new OS image with Gambas3 on it and getting the hang of it I have managed to get the bar chart program running.  As before the Psion II is pretending to be the data-logger and is sending out random data in the format I have currently settled on. It works pretty well, but the RPi is being pushed close to its limits here and the mouse has a habit of becoming inactive.  Ultimately I think I will need to learn Python and go down that route using the widget approach to get a GUI output, but there is a pretty steep learning curve there. The next step is to finish off the touch monitor and get a module (driver) for the touch panel and the calibration program running on the RPi.

 I bought a couple of these little USB 2.0 hubs for £1 each in PoundWorld intending to adapt them to be powered hubs for use with RaspberryPi computers.  Alan here ( http://pihub.blogspot.co.uk/2012/06/raspberry-pi-power-supply-and-powered.html ) beat me to it, but I wanted to give it a go with a flying power socket.  As usual, heat-shrink sleeve comes in to save the day. I didn't like the original USB lead and plug so I bought a USB-to-Micro USB cable (again for £1) and cut it in half.  One end goes to power the RPi and the other is the input USB. The input USB has only 3 connections made, the red power wire is cut short and ignored.  I did connect the ground (GND) wire though because the purist in me doesn't like the idea of floating grounds (blame my MSc).   The output for power to the RPi via the micro USB plug only has the GND and +5v connections made and the other 2 signal lines were chopped short and ignored. The power input was made ...

The workshop is in a right state this week as a result of trying to clear out stuff and move some furniture back into the house for a study I am decorating, which should hopefully be finished tomorrow now that I have some more white emulsion paint. I was working on my Silvercrest/LG TV recorder this evening, which has developed a fault with the DVD recorder part.  The hard drive end works fine, which means it is worth trying to repair.  The odd thing is that I cleaned out the DVD drive, cleaned the lens on the laser and blew some air round everything and hay presto it started playing a DVD again out in the workshop.  15 minutes later I took it back into the living room and hey un-presto it has gone kaputt again.  This is typical.  Maybe the house just has bad karma. I will investigate further. DVD Drive model - MEZ36295702

Okay, I now have a working Gambas program that will read a formatted RS232 data stream and display the data as a dynamic bar chart.  To test this I rigged up my trusty old Psion II LZ and wrote a little OPL (Psion programming language) script to output a suitable random data stream.  The project is running on a laptop at the minute because I haven't gotten Gambas onto the RasberryPi yet and apparently it is quite slow, but I love the graphics. The system is designed to work with 8 sensors and the data is 10-bit (values between 0-1023), so the format of a data frame is (at the moment) 18 bytes as follows - - 'A' as the start character, the program reads data and ignores it until it receives an A; - Pairs of bytes representing the upper and lower 5 bits of the 8 10-bit data values; - 'B' as a terminating character. To avoid confusion and make debugging easier, the 5-bit data is sent as bytes in the decimal range 32-63.  The ASCII codes for A and B are 65 an...

I got around to finishing off the repair of the DVI/HDMI monitor and here it is re-assembled and running a test with the RaspberryPi computer.  The RaspberryPi is temporarily in a simple Lego box to keep it from being damaged.  The connecting HDMI-to-DVI-D video cable came out of DiscountNI of all places for just £2.99, which was a real result. The small (and very tidy) power supply came out of an obsolete PC and I re-wired the mains input and removed all of the output connections before re-connecting one disk drive power cable with 2 Molex male connectors on it to provide 12v and 5v to the monitor. At the monitor side, I stripped out the parts connecting the broken internal power supply to the main circuit board (mainly the isolating transformer) and re-cycled a Molex female connector from an old DVD drive as a power input connection.  Some heat-shrink sleeving and couple of cable ties to neaten things up and the monitor is now running off the external p...

Well, here's the proof that I finally got hold of a RaspberryPi computer (for £25 including p&p).  The odd arrangement of the monitor has its own story of course.  I was given this Hanns-G LCD monitor recently by another kind Freegler, but the power supply was faulty.  What made it worth fixing was the DVI interface which can be directly connected to HDMI and HDMI is what the RaspberryPi outputs. So I took it apart and found that it was basically running off 12v and 5v which was easy enough to test rig from an old mini-PC power unit.  The monitor has a good crisp image and once I tidy the wiring up a bit it will be fine for use with the RaspberryPi.  The HDMI-to-DVI cable was £2.99 out of a local discount shop.  Always worth a look in Poundland, World of Pound, Home Bargains and the other discount shops, you never know what they have. For the time being, we built a Lego box for the RaspberryPi, pretty much from scratch.  The sticker on th...

An early analysis has shown that we have saved £750 this winter in reduced fuel costs by installing the new multi-burning stove.  Taking into account that this was a mild winter, the whole install will break even in just over 3 years.  The oil tank was filled a year ago and is still 1/4 full (so around 900l used) and we have used roughly a tonne of coal, giving a total fuel cost of around £750 for winter heating.  This compares with around £1500 in the last winter when we were on oil only. Phoenix Gas have been delivering a mail shot in our area (again) offering a piped natural gas service.  When I 'phoned up (again) to order it they told me (again) that it isn't available in our area.   Should they consider targeted marketing perhaps?