1.5 Arduino Online Resource
1.5.1 Official Websites
1.5.2 Third Party Open Source Code & Tutorials
1.5.3 Atmel Chips' Data Sheet
1.5.4 AVR C Compiler Resource
1.5.5 Popular Tools
1.5.6 Official Forums
1.5.7 Popular Ecosystem Forums
1.5.8 Arduino Cheat Sheet

1.5.9 Evolution Tree for Arduino

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