Jeff Epler 239c8ff87f metro_m0_express: put back audiobusio
this now fits locally (though it's very close to capacity);
let's see what the CI says.

```
make BOARD=metro_m0_express clean && make BOARD=metro_m0_express  TRANSLATION=ja
...
253448 bytes used, 248 bytes free in flash firmware space out of 253696 bytes (247.75kB).
```
2020-08-12 19:11:33 -05:00
..
2020-07-27 18:05:13 +09:00
2020-08-04 18:42:09 -05:00
2018-05-23 11:57:35 -07:00
wip
2019-12-05 22:45:53 -05:00
2020-07-30 07:18:02 -05:00
2020-06-22 10:45:27 -05:00

SAMD21 and SAMD51
==================

This port supports many development boards that utilize SAMD21 and SAMD51 chips. See
https://circuitpython.org/downloads for all supported boards.


Building
--------

For build instructions see this guide: https://learn.adafruit.com/building-circuitpython/


Debugging
---------

For debugging instructions see this guide: https://learn.adafruit.com/debugging-the-samd21-with-gdb


Port Specific modules
---------------------

.. toctree::
    ../../shared-bindings/samd/index