When the measurement results are read from the `ALG_RESULT_DATA` register set including the STATUS register, the `DATA_RDY` flag in the STATUS register is already cleared during reading. Therefore it is not possible to check this flag after the `ALG_RESULT_DATA` has been read. Therefore the function `ccs811_read_iaq` always returned `CCS811_ERROR_NO_NEW_DATA` although the data were valid either after checking for new data with the function `ccs811_data_ready` or after triggering the Data Ready interrupt.
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