Reading light level fails if using the ONETIME modes

[gerritv]

These modes power down the chip after the level is read. The present code does not wake up the chip when reading the value in those modes.

I added a save of mode and changed the code in readLightLevel:

uint16_t BH1750::readLightLevel(void) {

    ...

    // Start transmission to sensor
    Wire.beginTransmission(BH1750_I2CADDR);
    switch (MODE) {
        case BH1750_ONE_TIME_HIGH_RES_MODE:
        case BH1750_ONE_TIME_HIGH_RES_MODE_2:
        case BH1750_ONE_TIME_LOW_RES_MODE:
        __wire_write((uint8_t)MODE);
        break;
    }
    // Read two bytes from sensor
    Wire.requestFrom(BH1750_I2CADDR, 2);

    ...
}

[gerritv]

Awesome, thank you!!!

[coelner]

Please add the right delay time for the one-time measurement (datasheet page 7 and page 5 )

[claws]

@coelner, if you know what to do you are welcome to submit a merge request with the proposed change.