How to Use WiringPi on Edge

What is WiringPi

WiringPi is a GPIO Controller basic on C Program. Originally a library for Raspberry Pie. Now we have migrated to Edge-V. You can control the 40 pin header by it. Of course, you can also directly control all GPIOs by modifying the code.

Begin to Use WiringPi

Control command

  • run gpio -h , you can see all the control command with WiringPi.
gpio: Usage: gpio -v
       gpio -h
       gpio [-g|-1] ...
       gpio [-d] ...
       [-x extension:params] [[ -x ...]] ...
       gpio [-p] <read/write/wb> ...
       gpio <mode/read/write/aread/awritewb/pwm/pwmTone/clock> ...
       gpio <toggle/blink> <pin>
       gpio readall
       gpio unexportall/exports
       gpio export/edge/unexport ...
       gpio wfi <pin> <mode>
       gpio drive <group> <value>
       gpio pwm-bal/pwm-ms 
       gpio pwmr <range> 
       gpio pwmc <divider> 
       gpio load spi/i2c
       gpio unload spi/i2c
       gpio i2cd/i2cdetect
       gpio rbx/rbd
       gpio wb <value>
       gpio usbp high/low
       gpio gbr <channel>
       gpio gbw <channel> <value>
GPIO  --> GPIO native number
wPi   --> WiringPi number
Mode  --> GPIO Mode ,`ALT` mean that this  pin defined as a special function
V     --> 1:HIGH 0:low 
PU/PD --> PU:pull up PD:pull down DSBLD:disabled PU/PD

Control by command

The code defaults to wPi mode control

Here’s an example of controlling wPi number 14.

  • run gpio mode 14 out
    Now, The wPi number 14 mode is out.
  • run gpio write 14 0 to change the pinout level
rk3399:/ # gpio mode 14 out
rk3399:/ # gpio write 14 0
rk3399:/ # gpio read 14
0
rk3399:/ # gpio write 14 1
rk3399:/ # gpio read 14
1

GPIO mode control

which controls all GPIOs directly by modifying the code as follows:

--- a/wiringPi/wiringPi.c
+++ b/wiringPi/wiringPi.c
@@ -793,7 +793,7 @@ int wiringPiSetup(void)
 
         initialiseEpoch();
 
-        libwiring.mode = MODE_PINS;
+        libwiring.mode = MODE_GPIO;
         return 0;
 }

Here’s an example of controlling gpio number 6,which control white LED lights on and off.
image
image

rk3399:/ # gpio mode 6 out
rk3399:/ # gpio write 6 0
rk3399:/ # gpio read 6
0
rk3399:/ # gpio write 6 1
rk3399:/ # gpio read 6
1

notes

WiringPi itself includes many functions, not just controlling the output of GPIO pins and reading pin levels. Here is only a simple introduction and use, more use needs to be explored by users themselves.

2 Likes

not finding the gpio command in the khadas ubuntu OS

Hello, WiringPi is already installed.
Go to programs/System Tools and open UXTerm.
Once the terminal is open, type gpio-h, hit enter. This will show the commands available in WiringPi. For more information, see here.