Recently, I was trying to figure out why not all of the analog pins on my Qwiic Micro boards were working properly. I started looking at the graphical datasheet and EAGLE board files and realized there a couple of small mistakes in the board defintion.
Issue:
A4 (D5) & A5 (D6) are tied to PA00 and PA01, but these pins don't actually have ADC functionality on the SAMD21E (see figure below). D7 is tied to PA04, which should be A4, but in variants.cpp looks to be mapped to A5.
Solution:
The Qwiic Micro only makes use of 5/6 available ADC pins. Both the board definition files and graphical datasheet should be updated to reflect the correct pins. I've included a table below of what I believe are the correct ADC/IO/GPIO pins combinations.
ADC
I/O Pin
Digial Pin
A0
PA02
D1
A1
PA06
D2
A2
PA05
D3
A3
PA07
D4
N/A
PA00
D5
N/A
PA01
D6
A4/A5
PA04
D7
Please let me know if you require additional clarificaiton.
adamgarbo
commented
2 years ago
Hi folks,
Recently, I was trying to figure out why not all of the analog pins on my Qwiic Micro boards were working properly. I started looking at the graphical datasheet and EAGLE board files and realized there a couple of small mistakes in the board defintion.
Issue: A4 (D5) & A5 (D6) are tied to PA00 and PA01, but these pins don't actually have ADC functionality on the SAMD21E (see figure below). D7 is tied to PA04, which should be A4, but in
variants.cpplooks to be mapped to A5.Solution: The Qwiic Micro only makes use of 5/6 available ADC pins. Both the board definition files and graphical datasheet should be updated to reflect the correct pins. I've included a table below of what I believe are the correct ADC/IO/GPIO pins combinations.
Please let me know if you require additional clarificaiton.
Cheers, Adam