More Data-logging Experiments

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This is just a quick post, really to link to the short video I made below showing my latest data-logging experiment, which takes in a number of technologies.

At the core is an Arduino Nano doing the actual logging with code derived from work I did using PIC microcontrollers a few years ago. There are two parts to this -

  • Reading up to 8 10-bit analogue values (range 0-1023);
  • Reading the frequency of a PWM signal.

These values are output serially 10 times per second (at 115200 bps) in what I call a data 'frame' which looks like -

<AABBCCDDEEFFGGHH>

Each frame has 18 bytes terminated by '<' and '>'. The pairs of letters represent a 10-bit value split into 2 5-bit nibbles and these values (0-31) have 64 added to them so that they are displayable ASCII characters to make debugging easier (range is decimal 64-95)

Putting these together gives the basis for a data-logging and dashboard display system for my (currently ignored) 1988 Toyota MR2, but it needs a display of some sort.

I bought my son a Prestigio Visconte tablet about 3 years ago which was running Windows 10, the intention being this could be used for schoolwork. That didn't really take off and during the Covid-19 lock down he became a Linux Mint convert using a repaired laptop I gave him. So I decided to have a go at putting Linux on it and Ubuntu seemed the best choice for a tablet. This took a bit of work as the boot UEFI is 32-bit and the operating system is 64-bit which is unusual. After the normal swearing, coffee and craft cider I got it working, all except the screen rotation (now locked) and the cameras (not needed).

Next stage back to my old friend Gambas3 the Linux equivalent to Visual Basic and a much overlooked language perfect for my needs. A bit of tinkering about and the usual reverse-engineering of other people's code (i.e. theft) and the result is in the video.

Video of Data-logging Experiment

Leave comments on the video if you like.

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