Failure to connect to BMP280 with ESP8266

Other Hardware Science and Measurement
1

Have looked all the posts regarding this and still can't solve it.
Have run a sketch to scan for I2C , result was 0x76.
This sketch produces the error:-

#include <Wire.h>
#include <SPI.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BMP280.h>

#define BMP_SCK 13
#define BMP_MISO 12
#define BMP_MOSI 11 
#define BMP_CS 10

//Adafruit_BMP280 bme; // I2C
Adafruit_BMP280 bme(BMP_CS); // hardware SPI
//Adafruit_BMP280 bme(BMP_CS, BMP_MOSI, BMP_MISO,  BMP_SCK);
  
void setup() {
  Serial.begin(9600);
  Serial.println(F("BMP280 test"));
  
  while (!bme.begin(0x76)) {  
    Serial.println("Could not find a valid BMP280 sensor, check wiring!");
    delay(1000);
  }
}
  
void loop() {
    Serial.print("Temperature = ");
    Serial.print(bme.readTemperature());
    Serial.println(" *C");
    
    Serial.print("Pressure = ");
    Serial.print(bme.readPressure());
    Serial.println(" Pa");

    Serial.print("Approx altitude = ");
    Serial.print(bme.readAltitude(1013.25)); // this should be adjusted to your local forcase
    Serial.println(" m");
    
    Serial.println();
    delay(2000);
}
And this is my project:-
![20240312_093622|666x500](upload://5U3p0c6dswIL7OX28PIG2lf85FM.jpeg)

The sensor was described as KLOVA GY-BME280-3.3 GY-BMP280-3.3.

I'm fairly new to this but have had a bmp180 running for months now.
Any advice would be appreciated.

2

I’m a bit confused ; the link for your sensor points to a device that runs on I2C bus and you found the address with an I2C scan , but your sketch is for SPI.
Can we see a picture of the actual sensor and how you have it wired

This might be useful

3

Thanks hammy,
Here is a photo of the whole setup.

20240312_093622
20240312_0936221920×1440 204 KB

4

If all is well load the Adafruit BMP280test sketch from the examples and run it. You will likely need SDO pulled high.

5

And, my apologies, I have actually been running the I2C setting.

I have just read here https://myesp8266.blogspot.com/2016/12/bmp280-and-esp8266.html that the SDO pin cannot be left floating. Have connected both the SDO and CSB to VCC and am now getting readings but they seem to be 3-4 Degrees C too high.

6

From the link that hammy provided, we read --
Note that this temperature measurement is used internally to calibrate the pressure and humidity sensors. Because the sensor self-heats, the measured temperature is usually slightly higher than the actual temperature. If this is critical to your project, compare the measured temperature to the actual temperature and apply an offset if necessary.

7

Thanks for all the information, very glad to get the BMP280 working. Will have to deal with the +2 to +4 degrees C error.

8

You need to mount the sensor in /on something to stop self heating , and you need to know if your reference for temperature is correct and measuring the same point .

9

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