[catching up]

David VanHorn wrote:

>> I'm transferring at 9600 baud.  Aren't the latter two insignificant at
>> > such a low frequency?  Over two-inch traces?
> 
> 
> No. The risetime and falltime of the edges have lots of high frequency
> energy.
> If you don't have a SOLID ground between the two devices, you can radiate
> like hell.
> The resistors are best when located close to the driving pin, rather than
> the driven pin, and end up optimal for fast signals at about 100 ohms,
> slower signals can use larger values. In your case, 4.7k would be good.

Good to know, thanks!  I'll start designing those in.
-- 
Timothy J. Weber
http://timothyweber.org
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