ESP8266 Community Forum

8< http://electronut.in/IoT-temp-sensor/

Or load up the Arduino IDE with ESP8266 support, drop the Arduino pro mini clone and use a DHT11. You could also use WeMos D1 board - cheap and neat.

David

3.3v to VCC and CH_PD
gnd to gnd (common)
serial to USB Tx to esp8266 Rx via 10k/20k voltage divider
serial to USB Rx to esp8266 Tx directly

I have to question the 10/20 divider
I would recommend a good logic level converter [ sparkfun has a good one]
I assume that the 20k is connected from esp rx to gnd .. Do you know the input reststance ?
if its 20 k then you will see only 1/2 of the signal level

xtal wrote:

3.3v to VCC and CH_PD
gnd to gnd (common)
serial to USB Tx to esp8266 Rx via 10k/20k voltage divider
serial to USB Rx to esp8266 Tx directly

I have to question the 10/20 divider

Me too, the values seem too high. The only way to really know is to put an oscilloscope probe on the ESP's RX in pin to see exactly what you're getting there.

Lots of ideas out there.

Simple Ohm's Law question : since it is 10K/20K divider, total is 30K, so the output will be 2/3, if input voltage is 5V, output will be 3.3V.