Bill,

On Sun, 15 Oct 2006 14:42:44 -0700, William "Chops" Westfield wrote:

>...
> There are three common algorithms that I know of for doing autobaud:
> 
> 1) As you describe, step through appropriate bit rates till you don't
>     get errors.
> 2) As above, except use the results in the shift register to glean
>     "hints" of the likely bit rate; just as output at the wrong speed
>     looks like garbage, specific input can also look like specific
>     character(s), and you can usually detect a fairly large range in
>     two keypresses or so.  Subject to lossage if there are unusual
>     parity/stopbit configurations, or particularly large ranges of
>     possible speed.

I believe that's why the Hayes commands always start with "AT" - they use the misreads to determine the error between the expected baud rate and 
the actual one.  I don't know what the misreads look like, but I understand they are pretty predictable.

Cheers,


Howard Winter
St.Albans, England


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