The YL105 datasheet reveals a sensor that is better for 80% of hobbyist and commercial indoor projects . It is robust, forgiving, and cheap. When paired with proper timing code and a clean power supply, it rivals sensors twice its price.
// Datasheet threshold: 30 µs is the boundary if(duration > 30) byte *data = byte; return true; yl105 datasheet better
bool readByte(uint8_t* data) uint8_t byte = 0; for (int i = 0; i < 8; i++) while(digitalRead(YL105_PIN) == LOW); // Wait for start of bit uint32_t startTime = micros(); while(digitalRead(YL105_PIN) == HIGH); uint32_t duration = micros() - startTime; The YL105 datasheet reveals a sensor that is
#define YL105_PIN 2 void startSignal() pinMode(YL105_PIN, OUTPUT); digitalWrite(YL105_PIN, LOW); delay(20); // Better: 20ms (exceeds 18ms requirement) digitalWrite(YL105_PIN, HIGH); delayMicroseconds(40); pinMode(YL105_PIN, INPUT); // Datasheet threshold: 30 µs is the boundary
Stop fiddling with external pull-ups and faulty libraries. Download the original YL105 datasheet, follow the timing diagrams above, and build humidity logging that just works. YL105 Arduino wiring, YL105 vs DHT22 latency, YL105 humidity calibration offset, best YL105 library GitHub