====== choix ======
 
  * https://www.fabriqueurs.com/la-temperature-monte/
  * http://www.kandrsmith.org/RJS/Misc/Hygrometers/calib_many.html


  * DHT11 DHT22 AM2302 Temperature Humidity Sensor ? https://www.carnetdumaker.net/articles/utiliser-un-capteur-de-temperature-et-dhumidite-dht11-dht22-avec-une-carte-arduino-genuino/
  * DHT22   Shield Humidity/temperature sensor, Data output on D4
  * BMP180 Shield  Pressure/temperature sensor with I2C interface (D1-SCL, D2-SDA). I2C address 0x77

====== shields ======
beau tableau explicatif en description
https://www.ebay.fr/itm/WeMos-D1-Mini-Mini-Pro-Compatible-Shields-Now-with-Triple-Base-and-ESP32/322536706047?hash=item4b18af8fff:m:mTDnl7ewzGuk9vFvBSGmXCA:rk:40:pf:0


====== SCH ======
 [[https://www.ebay.fr/itm/BME280-Digital-Sensor-I2C-SPI-Breakout-Temperature-Humidity-Barometric-Pressure/173360204536| veritable BM2280 (mai 2019)]]

{{:divers_elec:bme280:s-l1600.jpg?200|}}
{{:divers_elec:bme280:s-l500.jpg|}}

<code>
100% brand new and high quality
BME280, the precision sensor from Bosch, is soldered onto PCB.
Not only the pressure and the temperature, this sensor can measure humidity.
It uses both I2C and SPI (supports 3-, 4-wire SPI) interface
Specifications:
Supply Voltage: 1.8 - 5V DC
Interface: I2C (up to 3.4MHz), SPI (up to 10 MHz)
Operational Range:
Temperature: -40 to +85°C
Humidity: 0-100%
Pressure: 300-1100 hPa
Resolution:
Temperature: 0.01°C
Humidity: 0.008%
Pressure: 0.18Pa
Accuracy:
Temperature: +-1°C
Humidity: +-3%
Pressure: +-1Pa
I2C address
SDO LOW ： 0x76
SDO HIGH：　0x77
</code>

====== driver ======
  * celui de adafruit pour adruino like : https://github.com/adafruit/Adafruit_BME280_Library
     * https://learn.adafruit.com/adafruit-bme280-humidity-barometric-pressure-temperature-sensor-breakout/arduino-test
  * https://github.com/BoschSensortec/BME280_driver

====== Temperature accuracy ======

  * https://github.com/letscontrolit/ESPEasy/issues/164
  * https://forum.arduino.cc/index.php?topic=558266.0
  * http://www.kandrsmith.org/RJS/Misc/Hygrometers/absolutetemperature.html
  * https://www.esp8266.com/viewtopic.php?f=13&t=8030&start=28
  * https://forum.arduino.cc/index.php?topic=448347.0

<code>
mise au point du BME 280

gris:22,5  RH30/51   1W en mode 3 fils
DS 23.12*c23.06*c  BME T:23.33*C P:99572Pa Rh:39.56%  BMP T:24.16*c P:99383

 matin au boot : gris 20,8    Rh29/50   
20.87*c20.94*c  BME T:20.75*C P:99337Pa Rh:45.95%  BMP T:21.11*c P:99164
15 minute plus tard gris 21 Rh27
21.75*c21.62*c  BME T:22.10*C P:99348Pa Rh:41.54%  BMP T:22.71*c P:99153


pooling 2s : BME en mode force et parasite power pour le 1W
Tgris23,7
 23.62*c23.25*c  BME T:23.50*C P:100085Pa Rh:44.79%  BMP T:24.49*c P:100015 

Gris 23,7 RH 41
23.25*c23.19*c  BME T:23.36*C P:100060Pa Rh:47.32%  BMP T:24.40*c P:100002

one wire parasite power ne fonctionne pas sur D4
</code>

====== arnaque au BMP280 vs BME280 ======
https://goughlui.com/2018/08/05/note-bosch-sensortec-bmp280-vs-bme280-sensor-confusion/

chip you have send me are not BME280 but BMP280 , there is no humidity available (chip id is 0x58 instead 0x60) the marking on the chip begin with K as written on BMP280 datasheet Page 41. so i ask refund of the order or sending me 3 reals BME280 with marking U as written on BME280 datasheet Page 44. regards