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Make’n Something with LIDAR [4: storing the data]

Alright, I'm talking to the LIDAR just like I said I wanted to. I can complete a full 360 scan..now what?

I'm not totally sure. I am happy that I got things working but I should probably do more with this device than just prove it out. I guess my next step depends on the application I want to use the LIDAR for. Until I figure that out, I just have an endless data stream that does nothing.

One thing I can do to that data is store it for later analysis. So that's my next step. Store data.

I had a feeling I would want to store the data, so when I bought the LIDAR I also bought this little microSD and RTC breakout board. It uses SPI to talk to the SD card, so I needed to go back and initialize SPI and its respective clocks and interrupts.

I ended up using FATFS to save the data in a human readable format. That's another abstraction layer. I save the data as a comma separated variable list so that I can easily import into Excel or Matlab later on.

I get 4000 samples per second, each 5 bytes long [20,000 bytes per second]. I don't think offloading the data to the SD card for later analysis is practical but it works for now. The unit is stationary so hours of data are not needed to be stored, just a second or so.

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