README.md

GpioDriver for other boards

This project contains some full function(PULL-UP, PULL-DOWN) generic GPIO drivers, and it can provide faster GPIO access.

Documentation

• For Allwinner SoCs: SunxiDriver
• For Rockchip SoCs: RockchipDriver

Benchmarks

The test uses different GPIO drivers to quickly switch the state of GPIO, and uses an oscilloscope to measure the average frequency of GPIO externally.

SunxiDriver

Benchmarking with Orange Pi Zero, select GPIO 6 (Logical). The operating system is Armbian buster, Linux kernel version is 5.10.16, and .NET version is 5.0.3.

Drivers	Language	Library Version	Test Date	Average Frequency
SunxiDriver	C#	-	2020-02-20	185 KHz
SysFsDriver	C#	System.Device.Gpio 1.3.0	2020-02-20	692 Hz
LibGpiodDriver	C#	System.Device.Gpio 1.3.0 libgpiod 1.2-3	2020-02-20	81 KHz
wiringOP	C	35de015	2020-02-22	1.10 MHz

RockchipDriver

Benchmarking with Orange Pi 4, select GPIO 150 (Logical). The operating system is Armbian buster, Linux kernel version is 5.10.16, and .NET version is 5.0.3.

Drivers	Language	Library Version	Test Date	Average Frequency
RockchipDriver	C#	-	2020-02-22	516 KHz
SysFsDriver	C#	System.Device.Gpio 1.3.0	2020-02-22	4.27 KHz
LibGpiodDriver	C#	System.Device.Gpio 1.3.0 libgpiod 1.2-3	2020-02-22	174 KHz
wiringOP	C	35de015	2020-02-22	584 KHz

Usage

Hardware required

• Orange Pi Zero
• Switch
• Male/Female Jumper Wires

Circuit

• Switch 1 - Board Pin7 (GPIO 6)
• Switch 2 - GND

Code

using System;
using System.Device.Gpio;
using Iot.Device.BoardLed;
using Iot.Device.Gpio.Drivers;

// Set debounce delay to 5ms
int debounceDelay = 50000;
int pin = 7;

Console.WriteLine($"Let's blink an on-board LED!");

using GpioController controller = new GpioController(PinNumberingScheme.Board, new OrangePiZeroDriver());
using BoardLed led = new BoardLed("orangepi:red:status");

controller.OpenPin(pin, PinMode.InputPullUp);
led.Trigger = "none";
Console.WriteLine($"GPIO pin enabled for use: {pin}.");
Console.WriteLine("Press any key to exit.");

while (!Console.KeyAvailable)
{
    if (Debounce())
    {
        // Button is pressed
        led.Brightness = 1;
    }
    else
    {
        // Button is unpressed
        led.Brightness = 0;
    }
}

bool Debounce()
{
    long debounceTick = DateTime.Now.Ticks;
    PinValue buttonState = controller.Read(pin);

    do
    {
        PinValue currentState = controller.Read(pin);

        if (currentState != buttonState)
        {
            debounceTick = DateTime.Now.Ticks;
            buttonState = currentState;
        }
    }
    while (DateTime.Now.Ticks - debounceTick < debounceDelay);

    if (buttonState == PinValue.Low)
    {
        return true;
    }
    else
    {
        return false;
    }
}