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Reading the temperature sensor value

Summary​

This is an example of reading analog temperature sensor value using ADC. Convert analog values ​​to Celsius and Fahrenheit using formulas. The converted value It is displayed on the screen through the serial port..

Materials​

  • WIZwiki-W7500 board
  • USB cable
  • Breadboard
  • Jumper wire
  • Temperature Sensor TMP36GT9 (Low Voltage Temperature Sensor)

Hardware​

Schematic​

The overall circuit diagram is as follows.

Connection diagram​

Software​

Example Code​

Here is an example code.

Open the page below and compile by importing the program with "Import this program".

🌎https://os.mbed.com/teams/IOP/code/Temp36_HelloWorld_WIZwiki-W7500/

Or, compile after copying and pasting the following code to main.c in the mbed environment.

/* Analog Input "Temp36" Temperature Sensor Example Program */
 
#include "mbed.h"
 
// Initialize a pins to perform analog input fucntions
AnalogIn   ain(A2); // connect A0(WIZwiki-W7500) to Vout(Temp36)
 
int main(void)
{
    while (1)
    {
        float V = ain.read(/) * 3.3; // connect Vs(Temp36) to 3.3V(WIZwiki-W7500) 
        //float V = ain.read(/) * 5; // connect Vs(Temp36) to 5V(WIZwiki-W7500)
        
        float tempC = (V-0.5) * 100; // calculate temperature C
        float tempF = (tempC * 9 / 5) + 32.0; // calculate temperature F
        
        printf("tempC value : %5.2f C \r\n", tempC);
        printf("tempF value : %5.2f F \r\n", tempF);
        
        wait(1.0);
    }
}

Methods and results​

The following is an example execution screen. Celsius and Fahrenheit temperature values alternate.

Learning materials​

See the link below for temperature sensor data.

  • [Kit Configuration Data Sheet] (/)