Here is a drawing/sketch of a fully functional “always-on” recorder. For now, I am just shooting to get the stand-alone portion working and recording locally (no cloud transfer) before I leave for Spring Break in two weeks.
With Danny’s help, I was able to get a sketch running in Processing that begins recording immediately. It saves the files as a pre-determined length with a manageable amount of dropped samples for the purposes of this device. I would like to make some way of having them overlap, but what could cause troubles when they’re being recombined. Danny and I also talked about a way to make a “mark” on each file so that you would know where and what to look for, like a button that appends a “check me” string onto the end of the file name. I could also knock the machine to make a loud sound which would be visible in an audio editor or could open a gate once the audio is analyzed.
On Sunday, I picked up a Raspberry Pi 3 Model B V1.2 from the ER, but once I got it home, I wasn’t able to power it on. I checked that my PSU was strong enough and reformatted the SD card and reloaded the OS, but nothing worked. I came back to ITP, got another Pi, this time it turned on, so I took it home and again, nothing. It would power on, but would not boot.
So today I came back and got a 3rd Pi, and Roland in the shop was able to help me get the OS up and running. First we tested that the Pi worked as another student (Mark from class) had a working Pi OS on an SD card. So once this new Pi booted up successfully, it was clear that my SD card was the problem. Roland directed me to go download Etcher which would reformat my SD card properly. I also downloaded the Stretch OS for Pi this time and not the NOOBS OS. I was able to load the OS ZIP file into Etcher and it formatted my SD card in a few minutes and… Pi booted up! I wish the Raspberry Pi website knew to direct folks to Etcher! I did not have time at school to test the Pi, but hopefully, during the next class, I can get the Processing sketch onto this Pi.