NETSERIALCOMM.EXE: problem with comm port not availabe to other ap

[Guest]

I am trying to use the software from John Hind's article: "Use P/Invoke to
Develop a .NET Base Class Library for Serial Device Communications".

When I use my application, everything works fine. I can open and close and
reopen the session with the internal modem with no problems. However, once my
application has been run, Hyperterminal and other modem-related programs will
not connect to the modem. Even if I terminiate my application, the problem
still persists.

Any ideas?

David

 

[md]

Are you sure your app is ending? If you look in Task Manager is it still
there? It sounds like your app isn't ending correctly and is holding the
serial port open. If you do the same thing in the IDE does the app end
correctly? I found that when an app ends in the IDE the IDE seems to handle
closing the port.

Matt

 

[Guest]

Yep. The app is ending. It shouldn't have to end, since it looks like the
close code does everything it is supposed to do. Once I have dialed one
number, the only way to get Hyperterminal working again is to go to the
control panel and run the diagnostics. That "unblocks" the modem so that
Hyperterminal can connect to it.

David

 

[Guest]

I'm not sure I believe it, but removing "Q1" from my modem initialization
string eliminates the problem. "Q1" was preventing Hyperterminal et. al. from
connecting to the modem.

David