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From:	shadow AT shadowgard DOT com
To:	opendos AT delorie DOT com
Date:	Tue, 17 Feb 2004 23:03:18 -0800
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Subject:	RE: X00 and other stuff, com speed with m$dos 6.22
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On 18 Feb 2004 at 13:10, da Silva, Joe wrote:

> 
> Hmmm ... If the program _doesn't_ mess around with the 
> UART registers, it _can't_ use anything higher than 19k2. 

Sure it can. If it uses the INT 14 calls to set the baud rate and to 
send bytes toand receive bytes from the serial port, then it will not 
*know* what rate the UART is actually running at. 

The *program* can think it's running at 19.2k. But X00 can run it at 
any rate it feels like.

Also, if you've got source or can find where the baud rate divisors 
are stored in a program, you can make a program that directly 
accesses UART registers work at higher baud rates. A common move was 
to replace the values for rates below 300 with those for rates 
*above* 19.2k


--
Leonard Erickson (aka shadow)
shadow at krypton dot rain dot com

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