Making it simpler to use multiple OneWire buses with an arduino array

OneWire.cpp

@@ -1,6 +1,12 @@
 /*
 Copyright (c) 2007, Jim Studt  (original old version - many contributors since)
 
+Modifications by Prashant : An extra no arguments constructor to simplify 
+multiple OneWire buse use, allowing for easier construction of arrays of OneWire buses,
+in the limited environment provided by Arduino.
+See the Multibus_simple example illustrating a use-case of the extension.
+Use in conjunction with my modification of the DallasTemperature library.
+
 Version 2.3: Modifications by Norbert Truchsess, January 2013
   add search_alarms() to find only devices in alarmed state.
 
@@ -122,7 +128,8 @@ sample code bearing this copyright.
 #include "OneWire.h"
 
 
-OneWire::OneWire(uint8_t pin)
+OneWire::OneWire() {}
+void OneWire::setPin(uint8_t pin)
 {
 	pinMode(pin, INPUT);
 	bitmask = PIN_TO_BITMASK(pin);
@@ -132,6 +139,11 @@ OneWire::OneWire(uint8_t pin)
 #endif
 }
 
+OneWire::OneWire(uint8_t pin)
+{
+	setPin(pin);
+}
+
 
 // Perform the onewire reset function.  We will wait up to 250uS for
 // the bus to come high, if it doesn't then it is broken or shorted

OneWire.h

@@ -126,6 +126,8 @@ class OneWire
 #endif
 
   public:
+    OneWire();
+    void setPin(uint8_t pin);
     OneWire( uint8_t pin);
 
     // Perform a 1-Wire reset cycle. Returns 1 if a device responds

README.md

@@ -1,5 +1,11 @@
 Copyright (c) 2007, Jim Studt  (original old version - many contributors since)
 
+Modifications by Prashant : An extra no arguments constructor to simplify 
+multiple OneWire buse use, allowing for easier construction of arrays of OneWire buses,
+in the limited environment provided by Arduino.
+See the Multibus_simple example illustrating a use-case of the extension.
+Use in conjunction with my modification of the DallasTemperature library.
+
 Version 2.3: Modifications by Norbert Truchsess, January 2013
   add search_alarms() to find only devices in alarmed state.
 

examples/Multibus_simple/Multibus_simple.ino

@@ -0,0 +1,48 @@
+#include <OneWire.h>
+#include <DallasTemperature.h>
+
+int oneWirePins[]={3,7};//OneWire DS18x20 temperature sensors on these wires
+const int oneWirePinsCount=sizeof(oneWirePins)/sizeof(int);
+
+OneWire ds18x20[oneWirePinsCount];
+DallasTemperature sensor[oneWirePinsCount];
+
+
+void setup(void) {
+  // start serial port
+  Serial.begin(9600);
+  Serial.println("Dallas Temperature Multiple Bus Control Library Simple Demo");
+  Serial.print("============Ready with ");
+  Serial.print(oneWirePinsCount);
+  Serial.println(" Sensors================");
+
+  // Start up the library on all defined bus-wires
+  DeviceAddress deviceAddress;
+  for (int i=0; i<oneWirePinsCount; i++) {;
+    ds18x20[i].setPin(oneWirePins[i]);
+    sensor[i].setOneWire(&ds18x20[i]);
+    sensor[i].begin();
+    if (sensor[i].getAddress(deviceAddress, 0)) sensor[i].setResolution(deviceAddress, 12);
+  }
+
+}
+
+void loop(void) {
+  // call sensors.requestTemperatures() to issue a global temperature 
+  // request to all devices on the bus
+  Serial.print("Requesting temperatures...");
+  for (int i=0; i<oneWirePinsCount; i++) {
+    sensor[i].requestTemperatures();
+  }
+  Serial.println("DONE");
+
+  delay(1000);
+  for (int i=0; i<oneWirePinsCount; i++) {
+    float temperature=sensor[i].getTempCByIndex(0);
+    Serial.print("Temperature for the sensor ");
+    Serial.print(i);
+    Serial.print(" is ");
+    Serial.println(temperature);
+  }
+  Serial.println();
+}