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#include "temphum.h"
#include "logging.h"
#include <Arduino.h>
namespace homekit::temphum {
static const int addr = 0x40;
void setup() {
pinMode(D2, OUTPUT);
pinMode(D3, OUTPUT);
Wire.begin(D2, D3);
Wire.beginTransmission(addr);
Wire.write(0xfe);
Wire.endTransmission();
delay(500);
}
struct data read() {
// Request temperature measurement from the Si7021 sensor
Wire.beginTransmission(addr);
Wire.write(0xF3); // command to measure temperature
Wire.endTransmission();
delay(500); // wait for the measurement to be ready
// Read the temperature measurement from the Si7021 sensor
Wire.requestFrom(addr, 2);
uint16_t temp_raw = Wire.read() << 8 | Wire.read();
double temperature = ((175.72 * temp_raw) / 65536.0) - 46.85;
// Request humidity measurement from the Si7021 sensor
Wire.beginTransmission(addr);
Wire.write(0xF5); // command to measure humidity
Wire.endTransmission();
delay(500); // wait for the measurement to be ready
// Read the humidity measurement from the Si7021 sensor
Wire.requestFrom(addr, 2);
uint16_t hum_raw = Wire.read() << 8 | Wire.read();
double humidity = ((125.0 * hum_raw) / 65536.0) - 6.0;
return {
.temp = temperature,
.rh = humidity
};
}
}
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