PlatformIO开发笔记3：点亮LED（面向对象封装io函数）

本文介绍IO驱动的调用方法。本系列文章将系统阐述其开发环境的使用方法，并期待构建基于Arduino的C++嵌入式开发平台。

MCU：ATmega168PA

系统平台：Arduino

github:https://github.com/snmplink/StarrySky

---

一、开发步骤

1、io.h源码

#ifndef IO_H_
#define IO_H_

#include <Arduino.h>

enum io_port{PortA, PortB, PortC, PortD};
enum io_pin{Pin0, Pin1, Pin2, Pin3, Pin4, Pin5, Pin7};
enum io_direction{Input, Output};
enum io_level{Low, High};
enum io_resistor{no_pull, pull_up, pull_down};

#ifdef __cplusplus
extern "C"{

class CIO
{
public:
    io_port PortNumber;
    io_pin PinNumber;
    io_direction Dircetion;
    io_level Level;
    io_resistor Resistor;
    uint8_t ArduionPinNumber;
public:
    CIO(io_port PortNumber, io_pin PinNumber, io_direction Dircetion, io_level Level = High, io_resistor Resistor = no_pull);
    void Set_0(void);
    void Set_1(void);
    void Set_I(void);
};

class CIO_Output:public CIO
{
public:
    CIO_Output(io_port PortNumber, io_pin PinNumber, io_level Level = High);
};

class CIO_Output_OST:public CIO_Output
{
public:
	CIO_Output_OST(io_port PortNumber, io_pin PinNumber, io_level Level = High);
	void Open(void);
	void Shut(void);
	void Turn(void);
};

class CIO_Output_OST_Low:public CIO_Output_OST
{
public:
	CIO_Output_OST_Low(io_port PortNumber, io_pin PinNumber);
};

class CIO_Output_OST_High:public CIO_Output_OST
{
public:
	CIO_Output_OST_High(io_port PortNumber, io_pin PinNumber);
};

}
#endif
#endif

2、io.cpp源码

#include "io.h"

CIO::CIO(io_port PortNumber, io_pin PinNumber, io_direction Dircetion, io_level Level = High, io_resistor Resistor = no_pull)
{
    this->PortNumber = PortNumber;
    this->PinNumber = PinNumber;
    this->Dircetion = Dircetion;
    this->Level = Level;
    this->Resistor = Resistor;

/*
---------------------------------------------------------------------------------
|   D0  |   D1  |   D2  |   D3  |   D4  |   D5  |   D6  |   D7  |   D8  |   D9  |
- -------------------------------------------------------------------------------  
|   PD0 |   PD1 |   PD2 |   PD3 |   PD4 |   PD5 |   PD6 |   PD7 |   PB0 |   PB1 |
---------------------------------------------------------------------------------

---------------------------------------------------------------------------------
|   D10 |   D11 |   D12 |   D13 |   D14 |   D15 |   D16 |   D17 |   D18 |   D19 |
- -------------------------------------------------------------------------------  
|   PB2 |   PB3 |   PB4 |   PB5 |   PC0 |   PC1 |   PC2 |   PC3 |   PC4 |   PC5 |
---------------------------------------------------------------------------------

-------------------------
|   D20 |   D21 |   D22 |
- -----------------------
|   PB6 |   PB7 |   PC6 |
-------------------------
*/
    if (this->PortNumber == PortB)
    {
        if      (this->PinNumber == 0) this->ArduionPinNumber = 8;
        else if (this->PinNumber == 1) this->ArduionPinNumber = 9;
        else if (this->PinNumber == 2) this->ArduionPinNumber = 10;
        else if (this->PinNumber == 3) this->ArduionPinNumber = 11;
        else if (this->PinNumber == 4) this->ArduionPinNumber = 12;
        else if (this->PinNumber == 5) this->ArduionPinNumber = 13;
        else if (this->PinNumber == 6) this->ArduionPinNumber = 20;
        else if (this->PinNumber == 7) this->ArduionPinNumber = 21;
    }
    else if (this->PortNumber == PortC)
    {
        if      (this->PinNumber == 0) this->ArduionPinNumber = 14;
        else if (this->PinNumber == 1) this->ArduionPinNumber = 15;
        else if (this->PinNumber == 2) this->ArduionPinNumber = 16;
        else if (this->PinNumber == 3) this->ArduionPinNumber = 17;
        else if (this->PinNumber == 4) this->ArduionPinNumber = 18;
        else if (this->PinNumber == 5) this->ArduionPinNumber = 19;
        else if (this->PinNumber == 6) this->ArduionPinNumber = 22;        
    }
    else if (this->PortNumber == PortD)
    {
        if      (this->PinNumber == 0) this->ArduionPinNumber = 0;
        else if (this->PinNumber == 1) this->ArduionPinNumber = 1;
        else if (this->PinNumber == 2) this->ArduionPinNumber = 2;
        else if (this->PinNumber == 3) this->ArduionPinNumber = 3;
        else if (this->PinNumber == 4) this->ArduionPinNumber = 4;
        else if (this->PinNumber == 5) this->ArduionPinNumber = 5;
        else if (this->PinNumber == 6) this->ArduionPinNumber = 6;   
        else if (this->PinNumber == 6) this->ArduionPinNumber = 7;      
    }

    if (this->Dircetion == Output)
    {
        //引脚方向为输出，则设置输出方向，并初始化电平
        pinMode(this->ArduionPinNumber, OUTPUT);
        digitalWrite(this->ArduionPinNumber, this->Level);
    }
    else
    {
        //引脚方向为输入
        if (this->Resistor == no_pull)
        {
            //无上拉电阻
            pinMode(this->ArduionPinNumber, INPUT);
        }
        else if (this->Resistor == pull_up)
        {
            //上拉电阻
            pinMode(this->ArduionPinNumber, INPUT_PULLUP);
        }
        else
        {
            //下拉电阻，AVR不支持
        }   
    }   
}

void CIO::Set_0(void)
{
    digitalWrite(this->ArduionPinNumber, LOW);
}

void CIO::Set_1(void)
{
    digitalWrite(this->ArduionPinNumber, HIGH);
}

void CIO::Set_I(void)
{
    if (digitalRead(this->ArduionPinNumber) == HIGH)
    {
        this->Set_0();
    }
    else
    {
        this->Set_1();
    }
    
}

CIO_Output::CIO_Output(io_port PortNumber, io_pin PinNumber, io_level Level):CIO(PortNumber, PinNumber, Output, Level, no_pull) {}

CIO_Output_OST::CIO_Output_OST(io_port PortNumber, io_pin PinNumber, io_level Level):CIO_Output(PortNumber, PinNumber, Level) {}

void CIO_Output_OST::Open(void)
{
    if (this->Level == Low)
    {
        this->Set_1();
    }
    else
    {
        this->Set_0();
    }    
}

void CIO_Output_OST::Shut(void)
{
        if (this->Level == Low)
    {
        this->Set_0();
    }
    else
    {
        this->Set_1();
    }   
}

void CIO_Output_OST::Turn(void)
{
    this->Set_I();
}

CIO_Output_OST_Low::CIO_Output_OST_Low(io_port PortNumber, io_pin PinNumber):CIO_Output_OST(PortNumber, PinNumber, Low) {}
	
CIO_Output_OST_High::CIO_Output_OST_High(io_port PortNumber, io_pin PinNumber):CIO_Output_OST(PortNumber, PinNumber, High) {}

3、类结构

二、调用方法

1、建立HAL.h文件，可参照以下程序

#ifndef HAL_H_
#define HAL_H_

#include "io.h"

#ifdef __cplusplus
extern "C"{

class CLED:public CIO_Output_OST_High
{
public:
    CLED(void);
};

class CHAL
{
public:
    CLED LED;
};

}
#endif
#endif

2、建立HAL.cpp文件，可参照以下程序，在此文件中指定端口号和引脚号

#include "hal.h"

CLED::CLED(void):CIO_Output_OST_High(PortB, Pin4) { }

3、接下来，在main.cpp中直接调用即可

#include "target.h"

CTarget Target;

void setup() 
{
  
}

void loop() 
{
  Target.HAL.LED.Turn();
  Target.Delayms(100);
}

4、此程序编译后，与前述两个例子达到的效果是相同的，但程序可读性有极大提升，切按照芯片引脚号，进行程序设计。