GPIO usage

GPIO pin assignment

GPIO Pin distribution

SPI	PWM	I2C	LCD	GPIO NUM	NAME	PIN	PIN	NAME	GPIO NUM	UART	LCD	PWM	SPI
				N/A	+3.3V	1	2	+5V	N/A
		I2C_SDA		58	GPIO58	3	4	+5V	N/A
		I2C_SCL		57	GPIO57	5	6	GND	N/A
				55	GPIO55	7	8	GPIO5	5	UART_TX
				N/A	GND	9	10	GPIO6	6	UART_RX
				42	GPIO42	11	12	GPIO38	38		LCD_HSYNC
				43	GPIO43	13	14	GND	N/A
				47	GPIO47	15	16	GPIO54	54
				N/A	+3.3V	17	18	GPIO51	51
SPI_MOSI				52	GPIO52	19	20	GND	N/A
SPI_MISO				53	GPIO53	21	22	GPIO50	50
SPI_SCLK				48	GPIO48	23	24	GPIO49	49
				N/A	GND	25	26	GPIO56	56
				45	GPIO45	27	28	GPIO40	40
			LCD_VSYNC	37	GPIO37	29	30	GND	N/A
			LCD_DE	39	GPIO39	31	32	GPIO46	46			PWM0
	PWM1			59	GPIO59	33	34	GND	N/A
				63	GPIO63	35	36	GPIO36	36		LCD_CLK
				60	GPIO60	37	38	GPIO61	61
				N/A	GND	39	40	GPIO44	44

If pin multiplexing is required, please refer to: https://milkv.io/zh/docs/mars/getting-started/gpio_full_multiplexing

Configure GPIO

1. Perform the following operations to configure GPIO:

Take GPIO44 as an example.

$ cd /sys/class/gpio

$ echo 44 | sudo tee export

You can run the command ls /sys/class/gpio to list the GPIO directory, check whether gpio44 appears, and confirm that the export is successful.

совет

The 44 in the command is the sys number, corresponding to GPIO44

2. Set the direction of GPIO

Run the command echo "out" | sudo tee gpio44/direction to set the direction of GPIO44 to output.

Run the command echo "in" | sudo tee gpio44/direction to set the direction of GPIO44 to input.

You can check the set direction by running the command cat gpio44/direction .

3. Set the voltage of GPIO44

Run the command echo "1" | sudo tee gpio44/value to set the voltage of GPIO44 to a high level.

Run the command echo "0" | sudo tee gpio44/value to set the voltage of GPIO44 to a low level.

You can view the set value through the command cat gpio44/value .