D2 & D4 connections

[n9wxu]

I have discovered on the batch of these M0-Mini's I just bought that D2 -> PA8 and D4 -> PA14

I cannot find any version data or schematics to match this.

[RobertPatzke]

Compared to the schematic of Arduino Zero, where the Pins Dx are called TCC0-Wy and the numbering has to be derived from connector pins (J101, J102), D4 = J102.5 = TCC0-W0 is connected to PA8 and D2 = J102.3 = TCC0-W4 is connected to PA14.
But the schematic of Arduino M0 shows different (changed) assignments with D4 = JOL.5 = TCC0-W4 connected to PA14 and D2 = JOL.3 = TCC0-W0 connected to PA8.
For Arduino it is not a problem, because they may have any adaption in their variant-files. But for me, as I access the pins direct via ports, it is an issue.
Here it is, that the pin assignment in the ReadMe.md is that of Arduino M0 and not that of Arduino Zero.
But the assignments in Arduino Zero seem to be simply wrong, because compared to the pin numbers of the CPU and their meaning (see CPU datasheet) show, that D2->PA8->CPU.13 and D4->PA14->CPU.23 is correct.

Update 2022-04-19
Today I detected, that there is a mix of D2 and D4 with this board. I had to change the pin assignments in my header file to get values correct at the D2 to D5 pins (I use these 4 pins to show the value of a decimal turn switch connected at A0 to A3).

[jpmeijers]

I hit the same issue. D2 and D4 seem to be swapped.

[M-J-Bauer]

Adafruit SAMD21 'ItsyBitsy M0 Express' board has D2 = PA14 = MCU pin23 and D4 = PA08 = MCU pin13. This is compatible with the Arduino Zero board.

The RobotDyn SAMD21 M0-Mini board has D2 = PA08 = MCU pin13 and D4 = PA14 = MCU pin23. This is NOT compatible with the Arduino Zero board.

The schematic provided in this repository is incorrect (at least for the batch of SAMD21-M0-Mini boards which I tested). The labels D2 and D4 are reversed.