Raspberry Pi misc scripts and experiments
Branch: master
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Permalink
Type Name Latest commit message Commit time
Failed to load latest commit information.
kerberosio
pcspeaker
README.md

README.md

Introduction

This repository contains several experiments in the form of bash scripting and NodeJS code that I'm using with my Raspberry Pi 3. My main Raspberry Pi use is building a low-cost home surveillance system with the help of the lightweight kerberos.io software.

The kerberos.io surveillance system

This is actually composed of quite few elements:

  • Raspberry Pi 3 board
  • Raspberry NoIR camera v2
  • An infrared light so the camera can record in full darkness
  • A PC Speaker, do not confuse with desktop speakers

This repository is divied in folders.

kerberosio

kerberos.io is able to perform several action when motion is detected, that by default is saving a picture to disk, calling a webhook, enabling a GPIO signal or sending a TCP message. Last one is a good candidate to build custom actions upon motion detection.

When motion is detected, I though it would be good to:

  • Beep the PC Speaker.
  • Send a Slack push notification
  • Send an email with the captured picture attached

This is fairly easy to implement with the kerberos.io example of TCP Listener, a simple NodeJS program that listen a TCP port for messages sent by kerberos.io, executing whatever actions we want to.

I modified the example program in order to perform the three mentioned actions. These are the files involved:

  • listener.js. The main program. Wait for TCP message reception and then beeps, search for latest captured image, send Slack push notification and email with picture attached.
  • helper.js. Helper functions that allow to determine the most recent file in a folder.
  • beepmotion.sh. It's a script that beeps the PC Speaker via GPIO.
  • kerberosio_listener.service. A systemd configuration file for starting the listerner at boot time.
  • pushenable.js. kerberos.io is great, but having to enter the portal in order to enable or disable movement capture was really incovinient. This small program implements physical button enable/disable of the system, giving feedback through 2 LEDs and 1 buzzer (not the PC Speaker one).

pcspeaker

Playing with the PC Speaker is fun. I though I could emulate the Big Ben clock sound with the GPIO PC Speaker. I didn't know anything of what signaling a PC Speaker needed in order to sound, but Dale Mitchel Github repository came into rescue. I modified the script, changing the interactive input with a fixed one and put some friendly vars resembling musical notes. The files here:

  • bigbensound.sh. It will play the Big Ben sound depending current system clock.
  • tone.sh. Just for testing, it will play the tone given by command line.

Putting bigbensound.sh in your CRON each 15 minutes will give you a nice Big Ben emulator. I'm actually looking for other clock tones.

YouTube video link