Sonic Anemometer Blog

Welcome. There's certainly many better ways to do this. For now, this will suffice.

Status Update 27/6

• PRU Firmware
  • Basic first pass done, no testing on actual THS1206 yet
    • Basic initialization/reset
    • Read values as it is available
    • Store values in local RAM
    • Transfer data to ARM with RPMsg using character device (or at least trying)
  • TODO
    • Get data transfer working
    • More extensive configuration
    • Tx triggers
    • Synchronization (can just be a flag in a shared register)
    • Actual hardware testing
• Other sensors
  • TODO
    • Get existing libs working on my board (works for mentors)
    • Look into using kernel modules where available
    • Check out options like MAVLink
• Sensor Fusion
  • TODO
    • Pulse detection from ADC results
    • Calculate speed of sound

The way forward from here seems pretty clear.

• RPMsg stuff shouldn't bet too bad, I probably just need to start from a very small/simple example (like one from the pru-support-package, which does work for me) and build it up to what I need.
• Getting the other sensors working is a bit of an unknown, but it is certainly just a local problem.
• Fleshing out the PRU firmware should be relatively straightforward. It's mostly a matter of twiddling the right bits for initialization. The rest is just adding a few basic checks and loops on top of existing code.
• First major unknown will be getting the firmware to actually properly control the THS1206 for real. Unfortunately I don't have a scope, so I'll probably need to go find one.
• Second major unknown will be the pulse detection. The goal here is relatively simple, but the complexity is going to depend a lot on what actually comes out of the hardware.