Communication with arduino and OPC/SCADA?

Using Arduino Interfacing w/ Software on the Computer
13

ilde:
Hello!

yes, i can imagine where is the bug in the Arduino OPC Server. Could you send me your sketch or al least the line where you create the OPC Item? AddItem(....

I am creating a new site for the Arduino OPC Server at:

http://www.ArduinoOPC.com/

so you could use the support forum for news, updates and bug fixes

All the best
ilde

Hi ilde

Please see my sketch below. Any suggestions are welcome.

Just to recap: when the piece of code " if(currentMillis - previousMillis > 2000)" executes every 2 seconds the OPC tag quality changes from good to bad and back to good.

It seems like every time the onewire device is accessed the OPC quality changes.

Looking forward to your response.

Regards
an3s

#include <OPC.h>
#include <OneWire.h>
#include <DallasTemperature.h>

#define ONE_WIRE_BUS 10

OneWire oneWire(ONE_WIRE_BUS);                                                             // Setup a oneWire instance to communicate with any OneWire devices
DallasTemperature Sensors(&oneWire);                                                       // Pass our oneWire reference to Dallas Temperature.
DeviceAddress ThermometerAddr = { 0x28, 0x2C, 0x83, 0x04, 0x05, 0x00, 0x00, 0x6B };  // Assign the addresses of your 1-Wire temp sensors.

OPC aOPC;  // Declaring the OPC object

int Analogue;
long previousMillis = 0;

int callback(const char *itemID, const opcOperation opcOP, const int value)  // create a callback function for the OPCItem
{
  return Analogue;
}

void setup() {
  Serial.begin(9600);
  Sensors.begin();                                    // Start up the library
  Sensors.setResolution(ThermometerAddr, 12);   // set the resolution to 12 bit
  Sensors.requestTemperatures();                      // Getting Temperatures
   
  aOPC.setup();                                       // OPC Object initialization

  aOPC.addItem("store",opc_read, opc_int, callback);  // random OPCItem declaration
}

void loop() {
  
  aOPC.processOPCCommands();                      // OPC process commands
    
  unsigned long currentMillis = millis();
 
  if(currentMillis - previousMillis > 2000)           // Scan This peace of code only every 2 seconds
  {
    previousMillis = currentMillis;    
    Sensors.requestTemperatures();                    // Getting Temperatures
    Analogue = Sensors.getTempC(ThermometerAddr);
  }
   
}

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