BME280 output reading not changing

[itsclarelyme]

Hello!

I have some BME280 sensors reading on a custom board, however, the signals have not been correct with the library driver and I am looking for technical support for it.

I have installed the software from your github: https://github.com/BoschSensortec/BME280_driver and follow along with the instructions. I downloaded this 02/13/2020, so the library should be up-to-date.

I am controlling the BME through SPI and Particle board (C++), I haven't changed anything in the driver file yet but here are the SPI signal readings from the SPI_READ functions declared in the main script. 

Please let me know what could be the issue.

Another questions I have is that I was wondering if you can provide the equations to convert analog signals to temperature/pressure/humidity. I cannot seem to find a clear equation in the datasheet or any sort of documentation. 

Please let me know how I can resolve this. thank you!

[itsclarelyme]

Hello!

I looked into the signals that it is reading and noticed that the data collect burst read for register 0xF7 shows default (0x800000 0x800000 0x8000) 

Here is a sample of the signal read/write that the driver is initiating and what the signal output is:

Please let me know why the data readings are not started, the device is connected, and is responding as BME280_OK (0).

[handytech]

Could you please share a code snippet of your project (at least BME280 configuration and data read-out)? From your description alone, it seems like you may trigger only one measurement (e.g. setting the BME280 to forced mode will trigger a single measure then go back to sleep mode), then reading-out this data sample multiple times.

---

@itsclarelyme wrote:

Another questions I have is that I was wondering if you can provide the equations to convert analog signals to temperature/pressure/humidity. I cannot seem to find a clear equation in the datasheet or any sort of documentation. 

---

You can find the reference implementation directly in the sensor API you linked (e.g. BME280 humidity formula in floating point).

[Antek]

Hi,

I have similar problems. I  am able to read chip ID correctly, but when reading measurement registers I am keep getting 0x800..

I am using microchip EVB, my code is based on github code.

So my main while loop looks:

while (1)
{
rslt = bme280_set_sensor_mode(BME280_FORCED_MODE, dev);
if (rslt != BME280_OK)
{
// fprintf(stderr, "Failed to set sensor mode (code %+d).", rslt);
//break;
}

/* Wait for the measurement to complete and print data @25Hz */
dev->delay_us(40000, dev->intf_ptr);
rslt = bme280_get_sensor_data(BME280_ALL, &comp_data, dev);
if (rslt != BME280_OK)
{
// fprintf(stderr, "Failed to get sensor data (code %+d).", rslt);
//break;
}

print_sensor_data(&comp_data);
dev->delay_us(1000000, dev->intf_ptr);
}

Why are measurements still the same?

BR