[WriteLog] Transmit lockup when computer starts up

Floyd Sense sentek at sprintmail.com
Fri Apr 2 13:11:22 EST 2004

Windows apparently polls the COM ports at start up time looking for any new
devices that might have been added so that the appropriate drivers can be
loaded.  In this context, think of devices that need drivers, such as an
external modem rather than devices that DO NOT need drivers, such as your
interface box or your transceiver.  For Windows XP (and perhaps earlier
versions - not sure), Microsoft has published a change that you can make to
the Registry that will cause XP to NOT scan the COM ports for new devices
upon startup.  That means that Windows will no longer activate certain
interface lines when you boot up and you will never see the problem you
mentioned again.  You can still add devices requiring drivers manually and
they will work the same as always.

The change requires you to add a parameter value to the Registry entry for
each COM port you don't want scanned at boot time.  It was more of a
challenge than I expected because I found several definitions for the COM
ports in the Registry and the Microsoft information was of no help in
identifying which should be changed.  So, if you're not comfortable editing
the Registry, this change may not be for you.

If there's any interest in this change, I'll post the info here.  I've had
it installed for several months now and it works just fine.  I no longer
have to disable the interface box to avoid the PTT line being keyed when I
boot the PC.


----- Original Message ----- 
From: <W7OM at aol.com>
To: <writelog at contesting.com>
Sent: Friday, April 02, 2004 12:18 PM
Subject: [WriteLog] Transmit lockup when computer starts up

> When the computer starts  and my FT-1000MP is ON, the transmit comes on
> stays locked.  The only way to clear this is to turn the MP off, start WL
> go to ports and click OK.  [The computer is using Windows 95 and a
> port for keying and PTT.]
> It appears that during the windows startup that it poles all the ports.
> sure why it puts the PTT line in a steady keyed mode when WL is NOT
> yet.
> Got one suggestion to use SO2R box which isolates the MP from the
> But there should be an easier way.
> 73
> Rod
> W7OM at aol.com
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