Correct Pin for D4


Im developing a custom Board based on the ATSAMD21G18A (Arduino Zero).

I had a look on the schematics for the Zero. Although the schematic is actually hard to read (many referrers are changing throughout the pages, there are different types of links between the Net connectors (why?)) I managed to get a basic design done.

One thing that made me suspicious was D4. On the Pin Header for D4 it says "PA08_TCC0-W0" but this connector actually connects to Pin 23 which is "PA14". On the other Hand, PA08 has a connector labeled as PA14 connected.

So, to which Pin is D4 connected?

EDIT: In the Variant file it says "4 | ~4 | PA08 | | EIC/NMI" So it is PA08 and the schematic is wrong?


Hi tsaG,

If you're planning using the's Arduino/Genuino Zero bootloader and core files, then yes D4 is PA08 and D2 is PA14.

The Arduino Zero eagle schematic PDF is incorrect, please find attached the original Atmel schematic.

Arduino-Zero-schematic.pdf (779 KB)

I have reported this issue:

I have reported this issue:
Errors on Zero schematic · Issue #6218 · arduino/Arduino · GitHub

Thanks pert.