I will add to this: the Arduino ecosystem is more valuable in that it can be used with your own board design. Install the open source boot loader into somethin

I will add to this: the Arduino ecosystem is more valuable in that it can be used with your own board design. Install the open source boot loader into something like at atsamd21g18 and "sketches" can be downloaded into your own board. Want to use RPI ecosystem? Forget it, the hardware and bootloader are closed. I see CPUs from AllWinnder used in some of these R-PI near-clones, such as PcDuino4 Nano. Anyone have luck buying these chips?