Question

我正在尝试并行使用多个mcp23017芯片，但并非每次都使用相同数量的芯片。我的代码是针对一个地址（默认地址）完成的，但是对于使用多个地址，则需要声明另一个mcp实例，每个实例用于所有现有地址？因为这样，如果我使用的是8芯片，我的代码将非常大...我可以使用某种方式搜索所有地址（完成）的循环，并且对所有地址仅使用一个mcp实例？

/*
Name : Program for MCP23017 uC with Arduino Board
Version : v1_01
Date : 26.06.2019
Author : 

ALL RIGHTS RESERVED

NOTE : Install the Adafruit MCP23017 library
          1. Open the Arduino IDE
          2. Select 'Sketch' -> 'Include Library' -> 'Manage Libraries'
          3. Search for '23017'
          4. Click 'Install' button for the 'Adafruit MCP23017 Arduino Library...'
*/

// v1_02 - change commands handling
// v1_03 - add I2C Scanner 

#include "Wire.h"
#include "Adafruit_MCP23017.h"

Adafruit_MCP23017 mcp; // Create mcp0 instance : Chip 0

int dly = 250;

void setup() 
{

   Serial.begin(9600);
   Serial.println("Continental Timisoara - FF PSS ECC IE TE");
   Wire.begin();

 /// Scan I2C addresses

  byte error, address;
  int nDevices;

  Serial.println("Scanning...");

  nDevices = 0;
  for(address = 1; address < 127; address++ )
  {
    // The i2c_scanner uses the return value of
    // the Write.endTransmisstion to see if
    // a device did acknowledge to the address.
    Wire.beginTransmission(address);
    error = Wire.endTransmission();

    if (error == 0)
    {
      Serial.print("I2C device found at address 0x");
      if (address<16)
        Serial.print("0");
      Serial.print(address,HEX);
      Serial.print(address);
      Serial.println("  !");

      nDevices++;
    }
    else if (error==4)
    {
      Serial.print("Unknown error at address 0x");
      if (address<16)
        Serial.print("0");
      Serial.println(address,HEX);
    }    
  }
  if (nDevices == 0)
    Serial.println("No I2C devices found\n");
  else
    Serial.println("done\n");

 /// -------------------



   mcp.begin(0); // Start mcp on Hardware address 0x20 ( all pins LOW )

   for(int i = 0; i <= 7; i++) 
   {
    mcp.pinMode(i, OUTPUT);
   }

   for(int i = 8; i <= 15; i++) 
   {
    mcp.pinMode(i, INPUT);
   }

}

void loop() {

  if(Serial.available()>0)
  {
      String letter = "";

  while(Serial.available()>0)
  {
  letter +=char(Serial.read());
  delay(100);
  }

   // =========================================================================================

    String Command = "";
    Command = letter.substring(2,3);

    String Reset = "";
    Reset = letter.substring(1,4);

    if (Command == "A")
    {

     String sOutput_Port = "";
     sOutput_Port = letter.substring(4,5);
     int iOutput_Port = sOutput_Port.toInt();

     mcp.digitalWrite(iOutput_Port,HIGH);
     int iInput_Port = iOutput_Port + 8;
     if(mcp.digitalRead(iInput_Port)==HIGH)
        {
        String Show = "Channel ";
        Show.concat(sOutput_Port);
        Show.concat(" is ON");

        Serial.println(Show);        
        }
        else
        {
        Serial.println("NO VALIDATION"); 
        }

    }


  if (Command == "I")
    {

     String sOutput_Port = "";
     sOutput_Port = letter.substring(4,5);
     int iOutput_Port = sOutput_Port.toInt();


     mcp.digitalWrite(iOutput_Port,LOW);
     int iInput_Port = iOutput_Port + 8;
     if(mcp.digitalRead(iInput_Port)==LOW)
        {
        String Show = "Channel ";
        Show.concat(sOutput_Port);
        Show.concat(" is OFF");

        Serial.println(Show);        
        }
        else
        {
        Serial.println("NO VALIDATION"); 
        }

    }


  if (Reset == "RST")
    {

           for(int i = 0; i <= 7; i++) 
            {
              mcp.digitalWrite(i,LOW); // Set GPA0 to LOW
            }

        Serial.println("GPA0 is RESET to LOW");

    }

// =========================================================================================

    }  // exit if(Serial.available()>0)

} // exit void loop()

Answer 1

解决方案1：不要使用Adafruit_MCP23017库，请自己编写。

解决方案2：将一个函数更新到Adafruit_MCP23017.c（并声明到Adafruit_MCP23017.h），该函数将更新i2caddr变量。像这样：

void Adafruit_MCP23017::setAddr(uint8_t addr) {
    if (addr < 8) {
      i2caddr = addr;
    }
}

这将使您可以随时更改地址。

使用多个MCP23017芯片-解决问题

1 个答案: