Arduino Forth HAL
UPDATED: This page contains a Forth hardware abstraction level (HAL) much like the m328def.
FlashForth
UPDATED: FlashForth is a phenomenal Forth for learning how to use Forth in an embedded system.
Using the Three Values of Forth
Where I demonstrate the three values of Forth; speed, extensibility and interactive, to develop a better understanding of the ATmega328P.