demo1.md

short version

SSH to your pi and start a node.js web server that controls the LED.

• <PI_NAME> is name of Pi, e.g. rpip5
• Password for pi account: raspberry

ssh pi@<PI_NAME>.local
cd rgb-slider
screen -R
node index.js
<Ctrl>-a d

Details

ssh to pi

ssh pi@192.168.8.<###>
cd rgb-slider
screen -R

• <###> is number corresponding to your Pi's IP address.
• Password for pi account: raspberry

Launch node.js server

Now, run a node.js server that controls the RGB LED.

NOTE: The following steps assume you are in a screen session.

# create a new window
<Ctrl>-a c

# navigate to node.js project directory if you are not there
cd ~/rgb-slider

# launch the server
node index.js
# via raspi-demo Wi-fi, connect to address it outputs, like http://192.168.8.101:3000

# (options) DETACH from screen session
<Ctrl>-a d

An aside on screen commands

screen is a handy utility that will allow you to connect/re-connect to running shell sessions.

It can be used to leave a script running after detaching, which we will be doing with our node.js server.

Screen does most of its work using a "Command key" which is <Ctrl>-a ^A

Keystrokes	Action
<Ctrl>-a d	"D"etach
<Ctrl>-a a	<Ctrl>-a
<Ctrl>-a c	"C"reate another window
<Ctrl>-a <Ctrl>-a	Other window
<Ctrl>-a "	List windows
<Ctrl>-a A	Name this window
<Ctrl>-a ?	Show HELP

There are many additional commands

To re-attach to a detached screen session (or if none, start a screen session), in BASH you can run:

screen -R

You can also have multiple sessions connected to a single screen instance. You connect this way using:

screen -x