The Velleman VM205 has my interest because I’m working with small digital projects with low frequency signals and I want to be able to trace those. And hey, it’s cool when you can do that with equipment that one assembled oneself, isn’t it?
So, I set out to my favourite electronics shop and bought a Raspberry Pi 3 B, and a Raspberry Pi 7 inch touchscreen display to go with it, and, of course, the VM205.
The RPI came with a pre-installed micro SD card that offered Raspbian. I installed that and got it up and running. Then I followed these instructions to connect the VM205, so SPI is enabled. I then downloaded the software from the Velleman website and, after having made it executable, tried to run it. It gives a message:
bcm2835_init: Unable to open /dev/mem: Permission denied
The command “uname -a” gives me a kernel version of 4.9.35-v7+
Somewhere along the line I got a message about a missing library, so I had to (re-) install it, libDSL2…
Any thoughts? I would really like to use this configuration as my low-level logic analyser.