IO control based on WiringPi on the Allwinner H616 Walnut Pie development board

aleksib

IO control based on WiringPi on the Allwinner H616 Walnut Pie development board [Copy link]

 

## GPIO instruction WiringPi encapsulates the physical pins of Walnut Pi and defines its own set of pin numbers. To ensure code compatibility, the current pin definitions of Walnut Pi and Raspberry Pi are consistent. ## Compile and run C code Let's experience the compilation and running methods of WirngPi. First, create a test.c file in the current directory of Walnut Pi and enter the following content (this code implements the printing of "Hello WalnutPi information" in the terminal): ```c #include<stdio.h> intmain(void) { printf("Hello WalnutPi\n"); return0; } ``` Compile the code. Since WiringPi exists as a dynamic library, you need to add `-lwiringPi` when compiling. The following command compiles the test.c file in the current directory into an executable file test. ```bash gcc -Wall -o test test.c -lwiringPi ``` Run the program just compiled: ```bash sudo ./test ``` You can see that after execution, the terminal prints out: Hello WalnutPi Information:  ## Geany IDE (Walnut Pie local) The Walnut Pie desktop system is pre-installed with Geany IDE, which is located in the **Start--Development** column. Geany can be used to implement C programming and compile and run. Open Geany:  Create a new file, enter the following test code, and save it as a .c file. ```c #include<stdio.h> intmain(void) { printf("Hello WalnutPi\n"); return0; } ```  Then configure the C code compilation and build command with WiringPi. Open **Build--Set Build Command**:  Add **-lwiringPi** to the end of the **Build** command (note that it is case-sensitive). This command is used to generate an executable file. The complete command after adding it is: ```bash gcc -Wall -o "%e""%f" -lwiringPi ``` Add **echo "root" | sudo -S** before the **Execute** command (note that it is case-sensitive). This command is used to run the executable file (program) generated previously. The complete command after adding it is: ```bash echo"root"|sudo -S "./%e" ```  After the configuration is complete, click the **Build** button, and you can see the compilation result information below. If the compilation is successful, an executable file will be generated in the current directory.  Click the **Execute** button again, and you can see a new terminal pop up, printing the "Hello WalnutPi" message, indicating that the code has been successfully compiled and executed.  ## VSCode IDE (ssh remote) In addition to using the Geany IDE that comes with Walnut Pi, here is how to use VSCode IDE remotely. For the VScode IDE remote method, please refer to: [VSCode IDE (ssh remote)](https://walnutpi.com/docs/python/python_run#vscode-%E8%BF%9C%E7%A8%8B%E8%BF%9E%E6%8E%A5%E5%9F%BA%E4%BA%8Ewindows) section content, which will not be repeated here. VScode IDE needs to use commands in the terminal to compile. The advantage is that C programming is more intuitive and can be operated remotely: Write code: ```bash gcc -Wall -o test test.c -lwiringPi ``` Execute the program: ```bash sudo ./test ```  ## IO control### Light up the first LED ```c /* Experiment name: Light up the first LED Experiment platform: Walnut Pie Description: Light up the LED on the Walnut Pie development board */ #include<stdio.h> #include<wiringpi.h> // The onboard LED pin of Walnut Pi is coded as 33 #defineLED33 intmain(void) { printf("WalnutPi LED\n"); wiringPiSetup(); pinMode(LED, OUTPUT); digitalWrite(LED, HIGH);//light up, LOW off. return0; } ``` ### Buttons```c /* Experiment name: Button Experiment platform: Walnut Pi Description: Press the button to light up the LED, release it to turn off the LED */ #include<stdio.h> #include<wiringpi.h> // The onboard LED pin wPi of Walnut Pi is coded as 33, and the key KEY is 32 #defineLED33 #defineKEY32 intmain(void) { printf("WalnutPi Pi KEY\n"); wiringPiSetup(); pinMode(LED, OUTPUT); pinMode(KEY, INPUT); pullUpDnControl(KEY, PUD_UP);//Turn on the pull-up resistorwhile(1) { if(digitalRead(KEY)== LOW)//Key pressed{ digitalWrite(LED, HIGH);//Turn on the LED } else { digitalWrite(LED, LOW);//Turn off the LED } } return0; } ``` </wiringpi.h></stdio.h></wiringpi.h></stdio.h></stdio.h></stdio.h>

freebsder

Thank you for sharing. This library is very useful and solves many technical details.