I saw the RXCTR is incremented after I push the data to PUSHR, but RXCTR decremented suddenly without reading POPR.At the same time, the RFDF equals 1.
The datasheet shows "the RXCTR is decremented every time the POPR is read and incremented every time data is transfered to the RX FIFO".So I can't understand why the RXCTR is decremented without reading POPR?
Why does RFDF equal 1 when RXCTR is 0 ? Does RFDF remain 1 before writing 1 to clear it or it cleard by clearing TCF?I think datasheet should show this mechanism.
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