Arduino Yun - Sound Detector

Building an internet connected Sound Detector on an Arduino Yun using Node.js

Hardware installation

Connect your sound system to an analogue pin. If you're using the Arduino microphone connect the VCC-pin to the 3.3V pin (not the 5V, that one's comming from the USB power).

Software Installation

Install SFTP server on Arduino Yun

opkg update
opkg install openssh-sftp-server

(http://dev.mikamai.com/post/62145565365/how-to-install-an-sftp-server-on-arduino-yun)

Expand Disk Space to microSD

http://arduino.cc/en/Tutorial/ExpandingYunDiskSpace

Install Node.js on the Arduino Yun

opkg update
opkg install node

Install node-serialport

Don't install serialport using npm but use the precompiled version for the Yun:

opkg update
opkg install node-serialport

Install node-socket.io

Don't install socket.io using npm but use the precompiled version for the Yun:

opkg update
opkg install node-socket.io

Install other Node.js modules

Try to install other Node.js modules on your computer and then copy them to the Yun. Installing modules on can take up some time.

Install the node code

Copy the code to /www/sd/node-sounddetector/app

Disable the console on /dev/ttyATH0

Linux uses the /dev/ttyATH0 serial port as its main console (it displays booting data when you boot the Linux CPU). You have to disable it in order to use this as a communication channel between the Arduino chip and the Linux CPU.

Open /etc/inittab and comment out the following line:

ttyATH0::askfirst:/bin/ash --login

Change it to:

# ttyATH0::askfirst:/bin/ash --login

Run the code

Run the code at least once on your computer so that a fresh public/index.html is created. Make sure you copy it to the Yun.

Go to /www/sd/node-sounddetector/app and run:

NODE_ENV=production node app

Startup your node process everytime the Yun starts

Go the OpenWRT control panel of your Yun. Go to System, Local Startup and add the following line to /etc/rc.local just before exit 0:

NODE_ENV=production /usr/bin/node /www/sd/node-sounddetector/app/app.js  1>/www/sd/node-sounddetector/app.log 2>&1 &

Error fixes

Error opening terminal: xterm-256color

Execute:

export TERM=xterm

FATAL ERROR: Evacuation Allocation failed - process out of memory

Edit /usr/bin/node.

Change:

NODE_PATH=/usr/lib/node_modules /usr/bin/nodejs --stack_size=1024 --max_old_space_size=20 --max_new_space_size=2048 --max_executable_size=5 --gc_global --gc_interval=100 $@

To:

NODE_PATH=/usr/lib/node_modules /usr/bin/nodejs $@

Temporarily.