Rock3/CM3/e23/GPIO

    ROCK 3 >  ROCK 3 Compute Module >  Radxa E23 >  GPIO

General purpose input-output (GPIO) connector

Radxa E23 has a 40-pin expansion header. Each pin is distinguished by color.

GPIO number	Function4	Function3	Function2	Function1	Pin#	Pin#	Function1	Function2	Function3	Function4	GPIO number
				+3.3V	1	2	+5.0V
32		I2C3_SDA_M0	UART3_RX_M0	GPIO1_A0	3	4	+5.0V
33		UART3_TX_M0	I2C3_SCL_M0	GPIO1_A1	5	6	GND
21		SPI0_MISO_M0	PWM6	GPIO0_C5	7	8	GPIO0_D1	UART2_TX_M0			25
				GND	9	10	GPIO0_D0	UART2_RX_M0			24
97			SPI1_CS0_M1	GPIO3_A1	11	12	GPIO3_B4	I2C5_SDA_M0			108
20	UART0_RTSn	PWM5	SPI0_CS1_M0	GPIO0_C4	13	14	GND
22		SPI0_CS0_M0	PWM7_IR	GPIO0_C6	15	16	USB_OTG0_DM
				NC	17	18	USB_OTG0_DP
138	I2C4_SDA_M0	I2S2_SDI_M1	SPI3_MOSI_M0	GPIO4_B2	19	20	GND
136		I2S1_SDO1_M1	SPI3_MISO_M0	GPIO4_B0	21	22	GPIO2_C6	UART8_RX_M0	SPI1_CS1_M0		86
139	I2S2_SDO_M1	I2C4_SCL_M0	SPI3_CLK_M0	GPIO4_B3	23	24	GPIO4_A6	SPI3_CS0_M0	I2S1_SCLK_RX_M1		134
				GND	25	26	GPIO4_A7	SPI3_CS1_M0	I2S1_LRCK_RX_M1		135
14	PWM2_M1	I2C2_SDA_M0	SPI0_MOSI_M0	GPIO0_B6	27	28	GPIO0_B5	SPI0_CLK_M0	I2C2_SCL_M0	PWM1_M1	13
113		SPI1_MOSI_M1	I2S1_SDO2_M2	GPIO3_C1	29	30	GND
114	I2S1_SDO3_M2	SPI1_MISO_M1	UART5_TX_M1	GPIO3_C2	31	32	GPIO0_C3	PWM4			19
15			PWM0_M0	GPIO0_B7	33	34	GND
29				GPIO0_D5	35	36	GPIO0_B4	I2C1_SDA			12
30				GPIO0_D6	37	38	GPIO0_C1	PWM2_M0	UART0_TX		17
				GND	39	40	GPIO0_B3	I2C1_SCL			11

Rockchip RK3566 GPIO has 5 banks, GPIO0 to GPIO4, each bank has 32pins, naming as below:

GPIO0_A0 ~ A7 
GPIO0_B0 ~ B7
GPIO0_C0 ~ C7
GPIO0_D0 ~ D7
   
GPIO1_A0 ~ A7
....
GPIO1_D0 ~ D7

For Rockchip 4.19 kernel, the GPIO number can be calculated as below, take GPIO4_A7 (PIN26 on 40-PIN HEADER) as an example:

GPIO4_A7 = 4*32 + 0*8 + 7 = 135
(A=0, B=1, C=2, D=3)

To set GPIO4_A7 output

cd /sys/class/gpio
echo 135 > export
cd gpio135
echo out > direction
echo 1 > value     # output high
echo 0 > value     # output low

GPIO0_D5 GPIO0_D6 GPIO2_C2 pin voltage is 1.8V