Photon and si7021

Troubleshooting
1

I have a Photon with a si7021 using the ported Adafruit_Si7021 libraries the project also has the DIY Mall 0.96 I2C display. The si7021 displays on the display correctly. My questions are as follows.

si7021 Code:

#include "Adafruit_Si7021.h"
Adafruit_Si7021 sensor = Adafruit_Si7021();
int Tempature = 0;
int TempF = 0;

void setup()   {
sensor.begin();
}

void loop() {

// Tempature measurement
  Tempature = (sensor.readTemperature();
  TempF = (( Tempature*9.0)/5.0+32.0);

//Display Temp and Hum on OLED
  display.print("Hum: "); display.println(sensor.readHumidity(), 2);
  display.setCursor(0,40);
  display.print("Tmp: "); display.println(sensor.readTemperature(), 2);

Particle.publish("Tempature", String(Tempature) + " °C", 60, PRIVATE);

}

  1. When I create the Photon.publish is shows a reading of 2 °C?

  2. Why can I not convert it to °F?

2
  1. What’s the question? Is 2 degrees C incorrect?
  2. You did convert it to F with, TempF = (( Tempature*9.0)/5.0+32.0); So, what’s the problem?
2 Likes
3
  1. Yes 2 was incorrect.
  2. When I used the TempF it didn’t work.

I found a different library to use instead of using the Adafruit_Si7021 I used Particle_Si7021. The conversion is in the .cpp.

New Code:

#include "Particle_Si7021.h"
SI7021 sensor;


void setup()   {
sensor.begin();
}

void loop() {

// temperature is an integer in hundredths
  int temperature = sensor.getFahrenheitHundredths();
  temperature = temperature / 100;

// humidity is an integer representing percent
  int humidity = sensor.getHumidityPercent();

//Display Temp and Hum on OLED
  display.print("Hum: "); display.println(humidity);
  display.print("Tmp: "); display.println(temperature);

  Particle.publish("Tempature", String(temperature) + " °F", 60, PRIVATE);

}
4
  1. So why the question mark on statement 1?
  2. What didn't work? Did you get no value or a wrong value?
5

yes they all seem to be the wrong values.

6

In the si7021 library, the return types for temperature and humidity are float, not int. Please try again with your variables declared and float type and see if that helps.

2 Likes
7

Change of project…

I am fixing to implement the Nextion 2.4 Enhanced display. I have the first few screens built and I am wanting to test.

If I change the names of the objects in the .hmi I use then new name correct?