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#ifndef CONFIG_TARGET_ESP01
#include <Arduino.h>
#endif
#include <homekit/logging.h>
#include "temphum.h"
namespace homekit::temphum {
void BaseSensor::setup() const {
#ifndef CONFIG_TARGET_ESP01
pinMode(CONFIG_SDA_GPIO, OUTPUT);
pinMode(CONFIG_SCL_GPIO, OUTPUT);
Wire.begin(CONFIG_SDA_GPIO, CONFIG_SCL_GPIO);
#else
Wire.begin();
#endif
}
void BaseSensor::writeCommand(int reg) const {
Wire.beginTransmission(dev_addr);
Wire.write(reg);
Wire.endTransmission();
delay(500); // wait for the measurement to be ready
}
SensorData Si7021::read() {
writeCommand(0xf3); // command to measure temperature
Wire.requestFrom(dev_addr, 2);
uint16_t temp_raw = Wire.read() << 8 | Wire.read();
double temperature = ((175.72 * temp_raw) / 65536.0) - 46.85;
writeCommand(0xf5); // command to measure humidity
Wire.requestFrom(dev_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
};
}
SensorData DHT12::read() {
SensorData sd;
byte raw[5];
writeCommand(0);
Wire.requestFrom(dev_addr, 5);
if (Wire.available() < 5) {
PRINTLN("DHT12: could not read 5 bytes");
goto end;
}
// Parse the received data
for (uint8_t i = 0; i < 5; i++)
raw[i] = Wire.read();
if (((raw[0] + raw[1] + raw[2] + raw[3]) & 0xff) != raw[4]) {
PRINTLN("DHT12: checksum error");
goto end;
}
// Calculate temperature and humidity values
sd.temp = raw[2] + (raw[3] & 0x7f) * 0.1;
if (raw[3] & 0x80)
sd.temp *= -1;
sd.rh = raw[0] + raw[1] * 0.1;
end:
return sd;
}
}
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