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http://mcumix.blogspot.com/2016/07/reverse-engineering-24ghz-rf-chip-xn297.html Recently, new chip appeared in many models - XN297. Although this chip seems to be a clone of nRF24L01+ - it has the same pinout, uses the same 16MHz crystal, the datasheet, partially translated to Chinese, looks very similar to the original, the register set is the same - it is not compatible by radio format.

https://www.sparkfun.com/datasheets/Components/SMD/nRF24L01Pluss_Preliminary_Product_Specification_v1_0.pdf

DAC, maybe for barometer https://www.analog.com/media/en/technical-documentation/data-sheets/26071727fa.pdf