At 01:18 PM 26/02/2002 -0500, you wrote:
>On Tue, Feb 26, 2002 at 10:36:00AM -0500, Olin Lathrop wrote:
> > > The grief saving answer is no. The true answer is "maybe if the
> conditions
> > > are right." Conditions being that the bit rate is slow enough and there
> > > isn't drastic changes in temperature.
> >
> > The absolute bit speed has nothing to do with it.  The relative speed error
> > is what matters.  You'd like to be within 3%, whether that's 300 baud +-9,
> > or 115.2Kbaud +- 3500.
>
>But if you slow it down then the absolute amount of time before the error
>is exceeded is lengthened.
>
>Change your examples to a time scale by inverting:
>
>300 bPS cell width: 3.3333 ms +- 0.3ms
>115k bPS cell width: 0.00886805 mS +- 0.000256 ms
>
>There's several orders of magnitude more error available at the slower speed
>before you get bit errors.

Huh?? With the faster baud rate, the byte is over quicker so it's still
relative.
Every new byte is re-synced so the error is only over one byte. The percentage
of clock error is applied to both cases equally. 3% seems to be acceptable.

>So yes absolute bit speed does have something to do with it because you
>can get proper reception at 300 bPS far outside the error range for 115kbPS.

No, this would have more to do with line conditions. (noise,etc.)
Regards...

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