Direct GPIO access

[Direct GPIO access]

Hi @JulianR:

     This is the linux common functions. Need to echo the pin number to export and then show the gpio$number in the path.

Please reference the following website link and reference sample. Thank a lot!

--->  Website link for GPIO Programming: Using the sysfs Interface

https://www.ics.com/blog/gpio-programming-using-sysfs-interface

---> Examples

1. GPIO input control example

 

0, 8

GPIO: /sys/class/gpio/gpio8

TEST_CLKOUT2

GPIO0_B0

7

* Console command:

- Export the GPIO pin

echo 8 > /sys/class/gpio/export

- Set the GPIO pin to input mode

echo in > /sys/class/gpio/gpio8/direction

- Read input value:

cat /sys/class/gpio/gpio8/value

 

2. GPIO output control example

 

0, 8

GPIO: /sys/class/gpio/gpio8

TEST_CLKOUT2

GPIO0_B0

7

* Console command:

- Export the GPIO pin

echo 8 > /sys/class/gpio/export

- Set the GPIO pin to output mode

echo out > /sys/class/gpio/gpio8/direction

- Set value to GPIO pin:

echo 1 >  /sys/class/gpio/gpio8/value

- Read the GPIO value

cat /sys/class/gpio/gpio8/value

[I2C not working?]

@Albertortor00

          Please reference following information. Thank a lot!

sudo i2cdetect -y 1 

sudo i2cdetect -y 2

--> Tinker Board 2S should use the following command for i2c 6 and 7

sudo i2cdetect -y 6

sudo i2cdetect -y 7

And the others to 9, but on mi /dev/ directory, doesn't exist 6, or 7... (like you say on your post)

--> Could you help to reference the following information to enable i2c 6 and 7 

https://github.com/TinkerBoard/TinkerBoard/wiki/Developer-Guide#tinker-board-2-on-debian-os

WiringPi C library for Debian (Tinker Board 2S)

I2C WiringPi for C library for Debian

• Firstly, modify the /boot/config.txt file as following and then reboot to enable I2C6 (wiringPi only support 1 I2C interface).

##### Hardware Interface Config #####

## Note: uart4 and spi1 are the same pins. Set the latter one while both on. ##

intf:fiq_debugger=on
#intf:uart0=off
#intf:uart4=off
intf:i2c6=on
#intf:i2c7=off
#intf:i2s0=off
#intf:spdif=off
#intf:spi1=off
#intf:spi5=off
#intf:pwm0=off
#intf:pwm1=off
#intf:pwm3a=off
#intf:test_clkout2=off

[GPIO]

Hi doggedly:

    The following red parts pin are for I2S so that you can't control the pins by gpio ways because the hdmi audio card need the pins.

Thank a lot!

 

126		I2S0_SDO1	GPIO3_D6	29		30		GND
125		I2S0_SDO2	GPIO3_D5	31		32	GPIO4_C2	PWM0		146
150		PWM1	GPIO4_C6	33		34		GND
121		I2S0_FS	GPIO3_D1	35		36	GPIO2_C2	UART0_CTSN		82
149		SPDIF_TX	GPIO4_C5	37		38	GPIO3_D3	I2S0_SDI0		123
		GND		39		40	GPIO3_D7	I2S0_SDO0		127

[GPIO]

Hi doggedly:

Please reference the following table for Tinkerboard 2. If you have any problem, please let us know! 

 

GPIO number	Function2	Function1	GPIO	Pin#		Pin#	GPIO	Function1	Function2	GPIO number
		VCC3.3V_IO		1		2		VCC5V_SYS
73		I2C6_SDA	GPIO2_B1	3		4		VCC5V_SYS
74		I2C6_SCL	GPIO2_B2	5		6		GND
8		TEST_CLKOUT2	GPIO0_B0	7		8	GPIO2_C1	UART0_TXD		81
		GND		9		10	GPIO2_C0	UART0_RXD		80
83		UART0_RTSN	GPIO2_C3	11		12	GPIO3_D0	I2S0_SCLK		120
85		SPI5_TX	GPIO2_C5	13		14		GND
84		SPI5_RX	GPIO2_C4	15		16	GPIO2_C6	SPI5_CLK		86
		VCC3.3V_IO		17		18	GPIO2_C7	SPI5_CSN		87
40	UART4_TXD	SPI1_TXD	GPIO1_B0	19		20		GND
39	UART4_RXD	SPI1_RXD	GPIO1_A7	21		22	GPIO3_D4	I2S0_SDO3		124
41		SPI1_CLK	GPIO1_B1	23		24	GPIO1_B2	SPI1_CSN		42
		GND		25		26	GPIO0_A6	PWM3A_IR		6
71		I2C7_SDA	GPIO2_A7	27		28	GPIO2_B0	I2C7_SCL		72
126		I2S0_SDO1	GPIO3_D6	29		30		GND
125		I2S0_SDO2	GPIO3_D5	31		32	GPIO4_C2	PWM0		146
150		PWM1	GPIO4_C6	33		34		GND
121		I2S0_FS	GPIO3_D1	35		36	GPIO2_C2	UART0_CTSN		82
149		SPDIF_TX	GPIO4_C5	37		38	GPIO3_D3	I2S0_SDI0		123
		GND		39		40	GPIO3_D7	I2S0_SDO0		127