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TheAustrian / Wemos-D1-Mini-BME280-Weather-Station

Simple Weather Station Code using an ESP8266 and a BME280 sensor. Data is handled via PHP and stored in a MySQL database
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A0 connected to 5V? #10

Open jpedrodias opened 5 years ago

jpedrodias commented 5 years ago

The A0 was a 3.3V limit. Why is it connected to 5V? What is the 200k resistor doing there?

bandaangosta commented 3 years ago

Came here with the same question, but moved on since there was no answer. For future reference, I came back with an answer. Wemos board already has a voltage divider in A0 pin. So, connecting a 200 kohm from A0 to a source makes it suitable for reading roughly 5V and below inputs. See https://forum.arduino.cc/index.php?topic=649032.0