Twin SHT21 sensors

Projects Programming
1

the code and design is from Misenso

/*
*  Read the relative humidity and temperature values from two SHT21 sensors
*  with JeeLabs "Ports" library used for software I2C: 
*  http://cafe.jeelabs.net/sw/library_-_ports/
*
*/
#include <Ports.h>
#include "PortsSHT21.h"
SHT21 hsensor1 (1);
SHT21 hsensor2 (2);
float h, t;
void setup()
{
  Serial.begin(9600);
  Serial.println("Dual SHT21 Demo (softi2c)");
}
void loop()
{
  // Get data from first sensor
  Serial.print("Sensor1 – ");
  hsensor1.measure(SHT21::HUMI);
  hsensor1.measure(SHT21::TEMP);
  hsensor1.calculate(h, t);
    
  Serial.print("Humi(%RH): ");
  Serial.print(h, 1);
  Serial.print("   Temp(C): ");
  Serial.println(t, 1);
    
  // Get data from second sensor
  Serial.print("Sensor2 – ");
  hsensor2.measure(SHT21::HUMI);
  hsensor2.measure(SHT21::TEMP);
  hsensor2.calculate(h, t);
  
  Serial.print("Humi(%RH): ");
  Serial.print(h, 1);
  Serial.print("   Temp(C): ");
  Serial.println( t, 1);
  Serial.println();
  
  delay(4000);
}

http://www.misenso.com/prototyping/two-sht21-softi2c-arduino/76/

can someone break down the code and please explain what is going on?

2

can someone break down the code and please explain what is going on?

Seems pretty straightforward to me. What part(s) don't you understand?

3

I would like to add a second sensor but the SHT21s have fixed I2C addresses that are all the same.

In the example from the Misenso site, the sensors have their own pair of ports.