There is a bug in implementation of serial communication.
With setting of
there should be no timeouts used for ReadFile. That means if ReadFile is called, it should be not return until a byte is arrived. In the current implementation of PicoCom1, ReadFile return immediatly if no byte is available to read.
With NetDCU8, PicoMod1 and also x86 Windows-Systems, the behavior is like expected.