Jan-Erik Soderholm XA wrote:
> > Each edge resets some timer on receiver (well, processing each
> > Bit, but just a little); Non-resetting the timer triggers
> > interrupt to start receiving data packet.( Non-resetting the
> > timer is caused by long enough "0"). Perhaps there is a better
> > way to start receiving.
> >
> > Since receiver works at half transmitter frequency, it can see
> > only every other (i.e. data) transmitted bit.
>
> Isn't the receiver sampling the line three times each "bit" ?
> You have to have these three samples in the first half of
> each bit, not ? If not, you will always end up with
> at least one sample that is different from the other two ?
> And you don't know (or the UART don't know) if it's the single
> different value that is correct, or if it's the other two.
> I think it will always select the two similar, but in this case
> it can be the single different value that is the correct one,
> depending on how the three samples are spread inside the "bit".
>
> I might be missing something...

   The idea is that a receiver shifts data automatically on it's
own clock (half the transmitter frequency).
   How to trigger receiving? That's another question.

Mike.

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