[WriteLog] Belkin USB serial FSK

[Laurence 'Mike' Hammer]

At 08:02 PM 10/12/00 -0500, WA9ALS - John wrote:
>  However, testing just now shows some kind of "stuttering" FSK sigs to 
> the Belkin serial device.
>...
>If I just hit ALT-K and idle, the RS-232 TD lites and the monitored
>tones are normal.  However, if I type, there are long periods (?5-10
>sec) of JUST idle, then a burst of data, then more idle.


Sounds like the system is buffering data until it has enough to "justify 
sending" according to the OS's system optimization algorithms.  This 
behavior may or may not be something that can be corrected, or changed 
perhaps is a better word.

You have to keep in mind that the Win9x, NT, 2000 etc OS's don't allow the 
programmer to take direct, real-time, complete control of hardware like we 
could under DOS.  They made this choice because they didn't want two 
programs running in "multitasking mode" (quotes for reasons known to 
experienced programmers!) to try to control the same hardware device at the 
same time.  That's the reason why you get the "device in use" error if two 
programs try to use the sound card at the same time.

This buffering, optimizing behavior is a design "feature" of these 
OS'.  While some folks have found some very interesting and nonstandard 
ways to avoid these problems, it means you face an uphill battle trying to 
control hardware using these OS' in true real time, especially if you want 
to use the machine to run anything other than the one program of concern.

Mike  N2VR



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