Week 13 葉正聖老師示範

https://www.arduino.cc/en/Tutorial/InputPullupSerial

2015 互動技術 Week 13 Arduino InputPullupSerial
https://www.youtube.com/watch?v=eyKnjkjiIPE



https://www.youtube.com/watch?v=9QMqK7ja9LI



https://www.arduino.cc/en/Tutorial/AnalogReadSerial