[geeks] Suggestions for USB to serial adapter?

Jochen Kunz jkunz at unixag-kl.fh-kl.de
Sat Sep 5 02:06:13 CDT 2009


On Fri, 4 Sep 2009 16:55:39 -0700
Nadine Miller <velociraptor at gmail.com> wrote:

> It works decently, though sometimes, unplugging it will
> send a break to the Suns.
Unpluging what side?

If you unplug the USB first and then the RS232 side it is no surprise
to me that they sometimes send a break. If you unplug the USB side the
power supply for the USB-to-RS232 chip goes away. When the voltage
drops below the minimum supply voltage of the chip all strange and
undefined things can go on inside the USB-to-RS232 chip...

Then you have the problem of an unpowered RS232 transmitter connected
to an alive RS232 receiver. This may result in undefined signal
levels...
--


tsch|_,
       Jochen

Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/



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