The SAMD21 Microcontroller

While one usually thinks “ATmega328” when presented with “Arduino”, and that microcontroller does represent the highest volume of boards, more models use the SAMD21G18 microcontroller than any other. That’s 11 of 23 different Arduino boards.

So having finished the 37 Sensors book, and taken some time off for other things, I am back to writing. And this time it is a book covering the SAMD21 in a manner similar to the books in the Far Inside The Arduino series.

While the Arduino software library does its best to make these boards look like an Arduino Uno, it is really becoming quite a stretch! The core processor architecture is completely different (ARM Cortex M0+ instead of Atmel AVR), and the peripheral complement has different and more advanced features.

These boards run at 3 times the clock speed, which might imply they are three times faster, but performance does vary. The 32 bit architecture does make them much better for arithmetic. There is 8 times the flash program memory, and 16 times the RAM memory, but no EEPROM.

I will report back here as I progress. I had already started looking at this as some earlier blog posts show.