ATSAMC21 pinout

C21E 32-pin package

PIN	I/O	SUPPLY	XTAL	EIC	REF	ADC0	ADC1	AC	PTC	DAC	SDADC	SERCOM	SERCOM-ALT	TC/TCC	TCC	COM	AC/GCLK	CCL
IOMUX:				A				B				C	D	E	F	G	H	I
1	PA00	VDDANA	XOSC32K	EXTINT[0]									SERCOM1/PAD[0]	TCC2/WO[0]			CMP[2]
2	PA01	VDDANA	XOSC32K	EXTINT[1]									SERCOM1/PAD[1]	TCC2/WO[1]			CMP[3]
3	PA02	VDDANA		EXTINT[2]		AIN[0]		AIN[4]	Y[0]	VOUT
4	PA03	VDDANA		EXTINT[3]	ADC-DAC/VREFA	AIN[1]		AIN[5]	Y[1]
5	PA04	VDDANA		EXTINT[4]	SDADC / VREFB	AIN[4]		AIN[0]	Y[2]				SERCOM0/PAD[0]	TCC0/WO[0]	CCL0/IN[0]
6	PA05	VDDANA		EXTINT[5]		AIN[5]		AIN[1]	Y[3]				SERCOM0/PAD[1]	TCC0/WO[1]	CCL0/IN[1]
7	PA06	VDDANA		EXTINT[6]		AIN[6]		AIN[2]	Y[4]		AINN[0]		SERCOM0/PAD[2]	TCC1/WO[0]	CCL0/IN[2]
8	PA07	VDDANA		EXTINT[7]		AIN[7]		AIN[3]	Y[5]		AINP[0]		SERCOM0/PAD[3]	TCC1/WO[1]	CCL0/OUT[0]
11	PA08	VDDIO		NMI		AIN[8]	AIN[10]		X[0]/Y[16]			SERCOM0/PAD[0]	SERCOM2/PAD[0]	TCC0/WO[0]	TCC1/WO[2]		CCL1/IN[3]
12	PA09	VDDIO		EXTINT[9]		AIN[9]	AIN[11]		X[1]/Y[17]			SERCOM0/PAD[1]	SERCOM2/PAD[1]	TCC0/WO[1]	TCC1/WO[3]		CCL1/IN[4]
13	PA10	VDDIO		EXTINT[10]		AIN[10]			X[2]/Y[18]			SERCOM0/PAD[2]	SERCOM2/PAD[2]	TCC1/WO[0]	TCC0/WO[2]		GCLK_IO[4]	CCL1/IN[5]
14	PA11	VDDIO		EXTINT[11]		AIN[11]			X[3]/Y[19]			SERCOM0/PAD[3]	SERCOM2/PAD[3]	TCC1/WO[1]	TCC0/WO[3]		GCLK_IO[5]	CCL1/OUT[1]
15	PA14	VDDIO	XOSC	EXTINT[14]								SERCOM2/PAD[2]		TC4/WO[0]	TCC0/WO[4]		GCLK_IO[0]
16	PA15	VDDIO	XOSC	EXTINT[15]								SERCOM2/PAD[3]		TC4/WO[1]	TCC0/WO[5]		GCLK_IO[1]
17	PA16	VDDIO		EXTINT[0]					X[4]/Y[20]			SERCOM1/PAD[0]	SERCOM3/PAD[0]	TCC2/WO[0]	TCC0/WO[6]		GCLK_IO[2]	CCL0/IN[0]
18	PA17	VDDIO		EXTINT[1]					X[5]/Y[21]			SERCOM1/PAD[1]	SERCOM3/PAD[1]	TCC2/WO[1]	TCC0/WO[7]		GCLK_IO[3]	CCL0/IN[1]
19	PA18	VDDIO		EXTINT[2]					X[6]/Y[22]			SERCOM1/PAD[2]	SERCOM3/PAD[2]	TC4/WO[0]	TCC0/WO[2]		AC/CMP[0]	CCL0/IN[2]
20	PA19	VDDIO		EXTINT[3]					X[7]/Y[23]			SERCOM1/PAD[3]	SERCOM3/PAD[3]	TC4/WO[1]	TCC0/WO[3]		AC/CMP[1]	CCL0/OUT[0]
21	PA22	VDDIO		EXTINT[6]					X[10]/Y[26]			SERCOM3/PAD[0]		TC0/WO[0]	TCC0/WO[4]		GCLK_IO[6]	CCL2/IN[6]
22	PA23	VDDIO		EXTINT[7]					X[11]/Y[27]			SERCOM3/PAD[1]		TC0/WO[1]	TCC0/WO[5]		GCLK_IO[7]	CCL2/IN[7]
23	PA24	VDDIO		EXTINT[12]								SERCOM3/PAD[2]		TC1/WO[0]	TCC1/WO[2]	CAN0/TX	AC/CMP[2]	CCL2/IN[8]
24	PA25	VDDIO		EXTINT[13]								SERCOM3/PAD[3]		TC1/WO[1]	TCC1/WO[3]	CAN0/RX	AC/CMP[3]	CCL2/OUT[2]
25	PA27	VDDIN		EXTINT[15]											GCLK_IO[0]
27	PA28	VDDIN		EXTINT[8]											GCLK_IO[0]
31	PA30	VDDIN		EXTINT[10]									SERCOM1/PAD[2]	TCC1/WO[0]		CORTEX_M0P/SWCLK	GCLK_IO[0]	CCL1/IN[3]
32	PA31	VDDIN		EXTINT[11]									SERCOM1/PAD[3]	TCC1/WO[1]		CORTEX_M0P/SWDIO	CCL1/OUT[1]

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