Re: GSM short message from DAVE.SMS@MVHI.COM

Mike A. Harris (mharris@ican.net)
Sat, 1 Aug 1998 21:12:05 -0400 (EDT)

On Sat, 1 Aug 1998, Richard B. Johnson wrote:

> > 40 characters or so, but capital letters generate codes that have
> > more bits turned on resulting in a higher draw on the UART. Many
> ^^____________
>
> (char) 'A' == (char) 'a' & 95;
> (char) 'Z' == (char) 'z' & 95;
>
> He was trying to save bits! Upper case uses less bits, so the BPS can
> be higher if your communications channel is bit-limited like the
> Micro$oft browser.

Ahh, but everything is inverted on the phone line. A logic 1
(high) becomes a SPACE, and a logic 0 becomes MARK out of the
UART. If you measure consumption with a DSO like I have, you'll
see that it in fact wastes electricity.

So yes, ucase ascii uses less "1" bits than does lowercase ascii,
however it is inverted out of the UART. Check it with a scope.

--
Mike A. Harris  -  Computer Consultant  -  Linux advocate


Escape from the confines of Microsoft's operating systems and push your
PC to it's limits with LINUX - a real OS. http://www.redhat.com






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