sam d21 xplained pro into a Zero

Can I just flash the bootloader on a sam d21 xplained pro to turn it into a Zero or does the debug chip need to be upgrade as well?


I have a SAMD21_XPRO board with the Shield Adapter. I can build in Rowley Crossworks or in Keil for both M0_PRO and D21_XPRO.

The pin mapping is very different. In theory you could just add a d21_xpro/variant.cpp and the Arduino core could work with ZERO, M0_PRO, D21_XPRO boards. In practice, the SERCOM# channels are completely different. So you need different SPI and Wire and Serial libraries.

It all gets a little untidy. Incidentally, I get odd verifier errors from Rowley. Keil can upload the code with no warnings. AS6 gives no warnings.