I made some application to communicate with LED and switch.

Preparations to AVR

First, I wrote program to AVR using ArduinoIDE. When I push the button `B`,as for other time 'o' is send to a PC. And when 'L' had been sent from PC, LED turned on.

I checked at serial monitor.

code is here

application

processing

Processing is easy to use for a beginner. When the button was pushed, ellipse is displayed on, and mouse was clicked ,LED turned on.

code is here

javascript using SerialPort Server

I try to use SerialPort Server. here is reference. I tested code with I improved a sample.

The LED of the board blinks only when I push the button. I got the status of the button.

But, I couldn't greatly remodel it…

code is here

node.js

Time was up, when I set some library. I install express and serialport .