ESP8266 Community Forum

- Wed Feb 17, 2016 5:03 pm #41310 Still the same problem.

I have connected D3 (=GPIOO) to SDA and D4 (=GPIO2) to SCL.
Next I took two 4.7K resistors and pulled both up to 3V

I double-checked that the Adafruit_BME280.cpp is still calling Wire.begin(0,2);

But still all I get from the sketch is:

Code: Select allould not find a valid BME280 sensor, check wiring!

Soft WDT reset

ctx: cont
sp: 3ffefa10 end: 3ffefbf0 offset: 01b0

>>>stack>>>
3ffefbc0:  3fffdc20 00000000 3ffefc3c 40201ca9 
3ffefbd0:  00000000 00000000 3ffeebb4 40202e2a 
3ffefbe0:  00000000 00000000 3ffeebd0 40100114 
<<<stack<<<

 ets Jan  8 2013,rst cause:2, boot mode:(3,7)

load 0x4010f000, len 1264, room 16
tail 0
chksum 0x42
csum 0x42
~ld


- Wed Feb 17, 2016 5:11 pm #41312 Maybe your BME280 is defective ...
Do you have any other I2C devices to try, for example a GPIO expander such MCP23017, or an I2C EEPROM such as AT24C64 ?

- Wed Feb 17, 2016 5:14 pm #41313 I have one BME280, one BMP180 and two BME/P280 with 6 pins.
They all show the same behaviour.

And the BME280 works still fine on my arduino uno

- Wed Feb 17, 2016 5:29 pm #41315 Let forget the Adafruit_BME280 for now, and let concentrate to see if I2C is working.

Try the piece of code to scan I2C devices :

Code: Select allvoid setup() {
  Serial.begin(115200);
  Serial.println("Starting I2C !");
  Wire.begin(0, 2);
  for (byte address = 1; address < 127; address++) {
    Wire.beginTransmission(address);
    byte error = Wire.endTransmission();
    if (error == 0) {
      Serial.print("I2C device found at address 0x");
      if (address < 16)
        Serial.print("0");
      Serial.print(address,HEX);
      Serial.println("  !");
    }
    else if (error == 4) {
      Serial.print("Unknown error at address 0x");
      if (address < 16)
        Serial.print("0");
      Serial.println(address,HEX);
    }   
  }
}