If you use int16_t for a variable you know it’s 16 bits, regardless of which Arduino is being targeted. int8_t/uint8_t - a signed/unsigned type that is exactly 8 bits in size.

While newer Arduinos and Arduino compatibles (including the Hackaday.io Trinket Pro. Superliminal Advertising!) either have a chip capable of USB or rely on a V-USB implementation, the old fogies o… ...