Sistemi integrati - problema slave master rs485 arduino

salve, sto cercando di fare comunicare 2 arduino con l' rs485 questo è il mio sorgente:

master:

#include <SoftwareSerial.h>
/*-----( Declare Constants and Pin Numbers )-----*/
#define SSerialRX        10  //Serial Receive pin
#define SSerialTX        11  //Serial Transmit pin

#define SSerialTxControl 3   //RS485 Direction control

#define RS485Transmit    HIGH
#define RS485Receive     LOW

#define Pin13LED         13

SoftwareSerial RS485Serial(SSerialRX, SSerialTX); // RX, TX

int byteReceived;
int byteSend;

void setup()
{

	Serial.begin(9600);
	Serial.println("YourDuino.com SoftwareSerial remote loop example");
	Serial.println("Use Serial Monitor, type in upper window, ENTER");
	pinMode(Pin13LED, OUTPUT);   
	pinMode(SSerialTxControl, OUTPUT);    
	digitalWrite(SSerialTxControl, RS485Receive);
	RS485Serial.begin(127000);

}


void loop()
{
	digitalWrite(Pin13LED, HIGH);
	if (Serial.available())
	{
		byteReceived = Serial.read();
		
		if(byteReceived == 48)
		{
			digitalWrite(SSerialTxControl, RS485Transmit);
			RS485Serial.write(48);
			digitalWrite(Pin13LED, LOW);
			delay(10);
			RS485Serial.write(49);
			digitalWrite(Pin13LED, LOW);
			delay(10);
			RS485Serial.write(50);
			digitalWrite(Pin13LED, LOW);
			delay(10);
			RS485Serial.write(51);
			digitalWrite(Pin13LED, LOW);
			delay(10);
			RS485Serial.write(52);
			digitalWrite(Pin13LED, LOW);
			delay(10);
			RS485Serial.write(53);
			digitalWrite(Pin13LED, LOW);
			delay(10);
			RS485Serial.write(54);
			digitalWrite(Pin13LED, LOW);
			delay(10);
			RS485Serial.write(55);
			digitalWrite(Pin13LED, LOW);
			delay(10);
			RS485Serial.write(56);
			digitalWrite(Pin13LED, LOW);
			delay(10);
			RS485Serial.write(57);
			digitalWrite(Pin13LED, LOW);
			delay(10);
			digitalWrite(SSerialTxControl, RS485Receive); 
		}
		
	}
	
	if (RS485Serial.available())
	{
		digitalWrite(Pin13LED, HIGH);
		byteReceived = RS485Serial.read();
		Serial.write(byteReceived);
		delay(10);
		digitalWrite(Pin13LED, LOW);  
	}  

}

slave:

#include <SoftwareSerial.h>
#include <WString.h>
/*-----( Declare Constants and Pin Numbers )-----*/
#define SSerialRX        10  //Serial Receive pin
#define SSerialTX        11  //Serial Transmit pin

#define SSerialTxControl 3   //RS485 Direction control
#define RS485Transmit    HIGH
#define RS485Receive     LOW

#define Pin13LED         13

SoftwareSerial RS485Serial(SSerialRX, SSerialTX); // RX, TX

int byteReceived;
int byteSend;
int *data;
int counter = 0;


void setup()
{
  Serial.begin(9600);
  Serial.println("SerialRemote");
  
  pinMode(Pin13LED, OUTPUT);   
  pinMode(SSerialTxControl, OUTPUT);  
  digitalWrite(SSerialTxControl, RS485Receive);
  RS485Serial.begin(127000);
}


void loop()
{
  if (RS485Serial.available()) 
  {
    while(RS485Serial.available() > 0)
    {
      byteSend = RS485Serial.read();
      data[counter] += byteSend;
      digitalWrite(Pin13LED, HIGH);
      delay(10);              
      digitalWrite(Pin13LED, LOW);
      counter++;
    }
    
    digitalWrite(SSerialTxControl, RS485Transmit);  
    if(data[0] == 48)
    {
      RS485Serial.write(48);
      delay(10);
    }

    digitalWrite(SSerialTxControl, RS485Receive);   

  }
  
}

non riesco a capire come mai sulla seriale del master appare continuamente la lettera p quando dovrebbe comparire un 1 quando io scrivo 1 sulla seriale del master :S.

Come sono collegate le due schede? Lo standard RS485 non può essere gestito direttamente da Arduino.

avevo sbagliato a collegare l' rs485 nell arduino uno, l' ho messo su 3.3v poi l' ho spostato sul 5 e ha funzionato. che vuol dire che lo standard rs485 non può essere gestito da arduino?

questo è il sorgente che ora funziona.

Master:

#include <SoftwareSerial.h>
#define SSerialRX        10  //Serial Receive pin
#define SSerialTX        11  //Serial Transmit pin

#define SSerialTxControl 3   //RS485 Direction control
#define RS485Transmit    HIGH
#define RS485Receive     LOW

SoftwareSerial RS485Serial(SSerialRX, SSerialTX); // RX, TX

char charbuff;
char message;
String buffer;

void setup()
{
	pinMode(13, OUTPUT);   
	pinMode(SSerialTxControl, OUTPUT);

  digitalWrite(SSerialTxControl, RS485Transmit); // trasmetti

  Serial.begin(9600);
  RS485Serial.begin(127000);
}

void loop()
{

	if (Serial.available())
	{

		charbuff = (char)Serial.read();
		buffer = String(charbuff);

		if(buffer == "A")
		{
			digitalWrite(SSerialTxControl, RS485Transmit);  // Enable RS485 Transmit
			digitalWrite(13, HIGH);
			RS485Serial.print("A");          // Send charbuff to Remote Arduino   
			digitalWrite(SSerialTxControl, RS485Receive);  // Disable RS485 Transmit
			digitalWrite(13, LOW);
			delay(10); 
			buffer = "";
		}
	}


	if (RS485Serial.available()) 
	{
		message = RS485Serial.read();
		Serial.print(message);
	}
}

Slave:

#include <SoftwareSerial.h>
#define SRS485SerialRX        10  //RS485Serial Receive pin
#define SRS485SerialTX        11  //RS485Serial Transmit pin

#define SRS485SerialTxControl 3   //RS485 Direction control
#define RS485Transmit    HIGH
#define RS485Receive     LOW

SoftwareSerial RS485Serial(SRS485SerialRX, SRS485SerialTX); // RX, TX

char charbuff;
String buffer;

void setup()
{
	pinMode(13, OUTPUT);   
	pinMode(SRS485SerialTxControl, OUTPUT);

  digitalWrite(SRS485SerialTxControl, RS485Receive); // trasmetti

  RS485Serial.begin(9600);
  RS485Serial.begin(127000);
}

void loop()
{

	if (RS485Serial.available())
	{
		charbuff = (char)RS485Serial.read();
		if(charbuff != (char)-1)
		{
			buffer += String(charbuff);
		}
		if(buffer == "A")
		{
			delay(10);
			digitalWrite(SRS485SerialTxControl, RS485Transmit);  // Enable RS485 Transmit
			digitalWrite(13, HIGH);
			RS485Serial.print("B");          // Send charbuff to Remote Arduino   
			digitalWrite(SRS485SerialTxControl, RS485Receive);  // Disable RS485 Transmit
			digitalWrite(13, LOW);
			buffer = "";
		}
	}
}

Arduino lavora con segnali digitali, 1 e 0 sopra i 5.5V danneggi la porta, segnale differenziale deve coprire una gamma di valori piu ampia, proprio perché deve resistere ai disturbi che su livello differenziale si annullano, se puoi generare solo 5V e 0V non puoi generare e ricevere un vero segnale differenziale, tanto è vero che la RS232 viene solitamente gestita mediante MAX232 con gli AVR.

ok grazie

io non lo uso perche devo metterlo in un ambiente con disturbi ma per la distanza elevata che riesce a raggiungere, devo arrivare sopra i 100 mt.

ora ho modificato il sorgente così e va più veloce il comando con la risposta solo che non riesco a capire perche se io do il comando all arduino nano (slave a) 3-4 volte di seguito lui risponde velocemente se invece do il comando allo slave a e poi al b velocemente il b non risponde se invece io aspetto circa 1 secondo tra comando all a e poi al b il b risponde, eppure io guardo i led della direzione del segnale e va immediatamente a low quindi il b dovrebbe essere in grado di ricevere e trasmettere immediatamente :S.

questo è il sorgente master:

#include <SoftwareSerial.h>
#define SRS485SerialRX        10  //RS485Serial Receive pin
#define SRS485SerialTX        11  //RS485Serial Transmit pin

#define SRS485SerialTxControl 13   //RS485 Direction control
#define RS485Transmit    HIGH
#define RS485Receive     LOW

SoftwareSerial RS485Serial(SRS485SerialRX, SRS485SerialTX); // RX, TX

char charbuff;
String message;
String buffer;

void setup()
{
	pinMode(13, OUTPUT);   
	pinMode(SRS485SerialTxControl, OUTPUT);
	digitalWrite(SRS485SerialTxControl, RS485Receive); // trasmetti
	Serial.begin(9600);
	RS485Serial.begin(4600);
}

void loop()
{

	begin:
	if(digitalRead(SRS485SerialTxControl) != LOW)
	{
		digitalWrite(SRS485SerialTxControl, RS485Receive);
		RS485Serial.flush();
		Serial.flush();	
	}

	if(RS485Serial.available())
	{
		while(RS485Serial.available())
		{
			while(String(charbuff) != String((char)-1)) 
			{
				charbuff = (char)RS485Serial.read();
		  		if(String(charbuff) != String((char)-1))
		  		{
		  			Serial.print(charbuff);
		  		}
		  		if(String(charbuff) == String("\n"))
		  		{
		  			Serial.print(charbuff);
		  			RS485Serial.flush();
					Serial.flush();
					break;
		  		}
			}
		}
	}

	if (Serial.available())
	{

		charbuff = (char)Serial.read();
		buffer = String(charbuff);

		if(buffer == "A")
		{
			digitalWrite(SRS485SerialTxControl, RS485Transmit);  // Enable RS485 Transmit
			RS485Serial.print("A10");          // Send charbuff to Remote Arduino 
			RS485Serial.flush();  
			digitalWrite(SRS485SerialTxControl, RS485Receive);  // Disable RS485 Transmit
			buffer = "";
			goto begin;
		}
		if(buffer == "B")
		{
			digitalWrite(SRS485SerialTxControl, RS485Transmit);  // Enable RS485 Transmit
			RS485Serial.print("B10");          // Send charbuff to Remote Arduino   
			RS485Serial.flush();
			digitalWrite(SRS485SerialTxControl, RS485Receive);  // Disable RS485 Transmit
			buffer = "";
			goto begin;
		}
	}




}

slave a:

#include <SoftwareSerial.h>
#define SRS485SerialRX        4  //RS485Serial Receive pin
#define SRS485SerialTX        3  //RS485Serial Transmit pin

#define SRS485SerialTxControl 13   //RS485 Direction control
#define RS485Transmit    HIGH
#define RS485Receive     LOW

SoftwareSerial RS485Serial(SRS485SerialRX, SRS485SerialTX);

char byteBuffer;
String commandBuffer;

void setup()
{
	pinMode(13, OUTPUT);
	Serial.begin(9600);
	RS485Serial.begin(4600);
	digitalWrite(SRS485SerialTxControl, RS485Receive);
}

void loop()
{

	if(digitalRead(SRS485SerialTxControl) != LOW)
	{
		digitalWrite(SRS485SerialTxControl, RS485Receive);
	}

	if(RS485Serial.available())
	{
		if(digitalRead(SRS485SerialTxControl) != LOW)
		{
			digitalWrite(SRS485SerialTxControl, RS485Receive);
		}

		while(RS485Serial.available()) 
		{

			if(digitalRead(SRS485SerialTxControl) != LOW)
			{
				digitalWrite(SRS485SerialTxControl, RS485Receive);
			}
			
			byteBuffer = (char)RS485Serial.read();
	  		if(String(byteBuffer) != String((char)-1))
	  		{
	  			commandBuffer += String(byteBuffer);
	  		}
	  		else
	  		{
				break;
	  		}

	  		if(commandBuffer.length() == 3)
			{
				if(String(commandBuffer) == String("A10"))
				{
delay(10);
					Serial.println("mando");
					digitalWrite(SRS485SerialTxControl, RS485Transmit);
					RS485Serial.print("X12345678901234567890123456789012345678901234567890123456789012345678901234567890\n");
					RS485Serial.flush();
					digitalWrite(SRS485SerialTxControl, RS485Receive);
					commandBuffer = "";
					break;
				}
			}

			if(commandBuffer.length() > 3)
			{
				RS485Serial.flush();
				if(digitalRead(SRS485SerialTxControl) != LOW)
				{
					digitalWrite(SRS485SerialTxControl, RS485Receive);
				}
				commandBuffer = "";	
				break;
			}
		}
	}

}

slave b:

#include <SoftwareSerial.h>
#define SRS485SerialRX        4  //RS485Serial Receive pin
#define SRS485SerialTX        3  //RS485Serial Transmit pin

#define SRS485SerialTxControl 13   //RS485 Direction control
#define RS485Transmit    HIGH
#define RS485Receive     LOW

SoftwareSerial RS485Serial(SRS485SerialRX, SRS485SerialTX);

char byteBuffer;
String commandBuffer;

void setup()
{
	pinMode(13, OUTPUT);
	Serial.begin(9600);
	RS485Serial.begin(4600);
	digitalWrite(SRS485SerialTxControl, RS485Receive);
}

void loop()
{

	if(digitalRead(SRS485SerialTxControl) != LOW)
	{
		digitalWrite(SRS485SerialTxControl, RS485Receive);
	}

	if(RS485Serial.available())
	{
		if(digitalRead(SRS485SerialTxControl) != LOW)
		{
			digitalWrite(SRS485SerialTxControl, RS485Receive);
		}

		while(RS485Serial.available()) 
		{

			if(digitalRead(SRS485SerialTxControl) != LOW)
			{
				digitalWrite(SRS485SerialTxControl, RS485Receive);
			}
			
			byteBuffer = (char)RS485Serial.read();
	  		if(String(byteBuffer) != String((char)-1))
	  		{
	  			commandBuffer += String(byteBuffer);
	  		}
	  		else
	  		{
				break;
	  		}

	  		if(commandBuffer.length() == 3)
			{
				if(String(commandBuffer) == String("A10"))
				{
delay(10);
					Serial.println("mando");
					digitalWrite(SRS485SerialTxControl, RS485Transmit);
					RS485Serial.print("Z12345678901234567890123456789012345678901234567890123456789012345678901234567890\n");
					RS485Serial.flush();
					digitalWrite(SRS485SerialTxControl, RS485Receive);
					commandBuffer = "";
					break;
				}
			}

			if(commandBuffer.length() > 3)
			{
				RS485Serial.flush();
				if(digitalRead(SRS485SerialTxControl) != LOW)
				{
					digitalWrite(SRS485SerialTxControl, RS485Receive);
				}
				commandBuffer = "";	
				break;
			}
		}
	}

}