Hi all!
It is possible to use PB22 and PB23 as GPIO with something like that?
pinMode(PB22, OUTPUT);
pinMode(PB23, INPUT);
digitalWrite(PB22, digitalRead(PB23);
I'm designing a custom board and wanted to know if I could use those pins. In the Arduino Zero they're used for EDBG_SERIAL RX/TX.
Thanks 
Those can be accessed as pins 30 and 31 in the IDE.
You can see all the pin assignments in variant.cpp in this hidden directory on Win7:
C:\Users~username~\AppData\Local\Arduino15\packages\arduino\hardware\samd\1.6.0\variants\arduino_zero
/*
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* + Pin number + ZERO Board pin | PIN | Label/Name | Comments (* is for default peripheral in use)
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | | Digital Low | | |
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | 0 | 0 -> RX | PA11 | | EIC/EXTINT[11] ADC/AIN[19] PTC/X[3] *SERCOM0/PAD[3] SERCOM2/PAD[3] TCC0/WO[3] TCC1/WO[1]
* | 1 | 1 <- TX | PA10 | | EIC/EXTINT[10] ADC/AIN[18] PTC/X[2] *SERCOM0/PAD[2] TCC0/WO[2] TCC1/WO[0]
* | 2 | 2 | PA14 | | EIC/EXTINT[14] SERCOM2/PAD[2] SERCOM4/PAD[2] TC3/WO[0] TCC0/WO[4]
* | 3 | ~3 | PA09 | | EIC/EXTINT[9] ADC/AIN[17] PTC/X[1] SERCOM0/PAD[1] SERCOM2/PAD[1] *TCC0/WO[1] TCC1/WO[3]
* | 4 | ~4 | PA08 | | EIC/NMI ADC/AIN[16] PTC/X[0] SERCOM0/PAD[0] SERCOM2/PAD[0] *TCC0/WO[0] TCC1/WO[2]
* | 5 | ~5 | PA15 | | EIC/EXTINT[15] SERCOM2/PAD[3] SERCOM4/PAD[3] *TC3/WO[1] TCC0/WO[5]
* | 6 | ~6 | PA20 | | EIC/EXTINT[4] PTC/X[8] SERCOM5/PAD[2] SERCOM3/PAD[2] *TCC0/WO[6]
* | 7 | 7 | PA21 | | EIC/EXTINT[5] PTC/X[9] SERCOM5/PAD[3] SERCOM3/PAD[3] TCC0/WO[7]
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | | Digital High | | |
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | 8 | ~8 | PA06 | | EIC/EXTINT[6] ADC/AIN[6] AC/AIN[2] PTC/Y[4] SERCOM0/PAD[2] *TCC1/WO[0]
* | 9 | ~9 | PA07 | | EIC/EXTINT[7] ADC/AIN[7] AC/AIN[3] PTC/Y[5] SERCOM0/PAD[3] *TCC1/WO[1]
* | 10 | ~10 | PA18 | | EIC/EXTINT[2] PTC/X[6] +SERCOM1/PAD[2] SERCOM3/PAD[2] *TC3/WO[0] TCC0/WO[2]
* | 11 | ~11 | PA16 | | EIC/EXTINT[0] PTC/X[4] +SERCOM1/PAD[0] SERCOM3/PAD[0] *TCC2/WO[0] TCC0/WO[6]
* | 12 | ~12 | PA19 | | EIC/EXTINT[3] PTC/X[7] +SERCOM1/PAD[3] SERCOM3/PAD[3] TC3/WO[1] *TCC0/WO[3]
* | 13 | ~13 | PA17 | LED | EIC/EXTINT[1] PTC/X[5] +SERCOM1/PAD[1] SERCOM3/PAD[1] *TCC2/WO[1] TCC0/WO[7]
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | | Analog Connector | | |
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | 14 | A0 | PA02 | A0 | EIC/EXTINT[2] *ADC/AIN[0] DAC/VOUT PTC/Y[0]
* | 15 | A1 | PB08 | A1 | EIC/EXTINT[8] *ADC/AIN[2] PTC/Y[14] SERCOM4/PAD[0] TC4/WO[0]
Continued...
* | 16 | A2 | PB09 | A2 | EIC/EXTINT[9] *ADC/AIN[3] PTC/Y[15] SERCOM4/PAD[1] TC4/WO[1]
* | 17 | A3 | PA04 | A3 | EIC/EXTINT[4] *ADC/AIN[4] AC/AIN[0] PTC/Y[2] SERCOM0/PAD[0] TCC0/WO[0]
* | 18 | A4 | PA05 | A4 | EIC/EXTINT[5] *ADC/AIN[5] AC/AIN[1] PTC/Y[5] SERCOM0/PAD[1] TCC0/WO[1]
* | 19 | A5 | PB02 | A5 | EIC/EXTINT[2] *ADC/AIN[10] PTC/Y[8] SERCOM5/PAD[0]
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | | Wire | | |
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | 20 | SDA | PA22 | SDA | EIC/EXTINT[6] PTC/X[10] *SERCOM3/PAD[0] SERCOM5/PAD[0] TC4/WO[0] TCC0/WO[4]
* | 21 | SCL | PA23 | SCL | EIC/EXTINT[7] PTC/X[11] *SERCOM3/PAD[1] SERCOM5/PAD[1] TC4/WO[1] TCC0/WO[5]
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | |SPI (Legacy ICSP) | | |
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | 22 | 1 | PA12 | MISO | EIC/EXTINT[12] SERCOM2/PAD[0] *SERCOM4/PAD[0] TCC2/WO[0] TCC0/WO[6]
* | | 2 | | 5V0 |
* | 23 | 4 | PB10 | MOSI | EIC/EXTINT[10] *SERCOM4/PAD[2] TC5/WO[0] TCC0/WO[4]
* | 24 | 3 | PB11 | SCK | EIC/EXTINT[11] *SERCOM4/PAD[3] TC5/WO[1] TCC0/WO[5]
* | | 5 | | RESET |
* | | 6 | | GND |
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | | LEDs | | |
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | 25 | | PB03 | RX |
* | 26 | | PA27 | TX |
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | | USB | | |
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | 27 | | PA28 | USB_HOST_ENABLE | EIC/EXTINT[8]
* | 28 | | PA24 | USB_NEGATIVE | *USB/DM
* | 29 | | PA25 | USB_POSITIVE | *USB/DP
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | | EDBG | | |
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | 30 | | PB22 | EDBG_UART TX | *SERCOM5/PAD[2]
* | 31 | | PB23 | EDBG_UART RX | *SERCOM5/PAD[3]
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | 32 | | PA22 | EDBG_SDA | Pin 20 (SDA)
* | 33 | | PA23 | EDBG_SCL | Pin 21 (SCL)
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | 34 | | PA19 | EDBG_MISO | EIC/EXTINT[3] *SERCOM1/PAD[3] SERCOM3/PAD[3] TC3/WO[1] TCC0/WO[3]
* | 35 | | PA16 | EDBG_MOSI | EIC/EXTINT[0] *SERCOM1/PAD[0] SERCOM3/PAD[0] TCC2/WO[0] TCC0/WO[6]
* | 36 | | PA18 | EDBG_SS | EIC/EXTINT[2] *SERCOM1/PAD[2] SERCOM3/PAD[2] TC3/WO[0] TCC0/WO[2]
* | 37 | | PA17 | EDBG_SCK | EIC/EXTINT[1] *SERCOM1/PAD[1] SERCOM3/PAD[1] TCC2/WO[1] TCC0/WO[7]
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | 38 | ATN | PA13 | EDBG_GPIO0 | EIC/EXTINT[13] SERCOM2/PAD[1] SERCOM4/PAD[1] *TCC2/WO[1] TCC0/WO[7]
* | 39 | | PA21 | EDBG_GPIO1 | Pin 7
* | 40 | | PA06 | EDBG_GPIO2 | Pin 8
* | 41 | | PA07 | EDBG_GPIO3 | Pin 9
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | | | | |
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | | GND | | |
* | 42 | AREF | PA03 | | EIC/EXTINT[3] *[ADC|DAC]/VREFA ADC/AIN[1] PTC/Y[1]
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | |32.768KHz Crystal | | |
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
* | | | PA00 | XIN32 | EIC/EXTINT[0] SERCOM1/PAD[0] TCC2/WO[0]
* | | | PA01 | XOUT32 | EIC/EXTINT[1] SERCOM1/PAD[1] TCC2/WO[1]
* +------------+------------------+--------+-----------------+--------------------------------------------------------------------------------------------------------
*/
Thank you!
It is aslo possible to use those pins as a Serial port with a Serialsomething class?
I doubt it. Not hardware serial anyway. The library probably doesn't support it, just as the SPI library doesn't support the additional SPI port on pins 10-13.
You might be able to use a software serial lib. I think there should be one out there.