Teensy 3.1 and USB connect / disconnect

[bigredbee]

I have a simple program that loops on writing a string to the USB serial port.

I apply external battery power to the Teensy

a) Now plug in the USB cable: windows installs the com-port as seen in the device manager
b) run TeraTerm and connect to the newly installed com-port.

All is well -- and I see the string being repeatedly sent from the teensy.

c) now unplug the USB cable, it disappears from device manager
d) now plug it back in -- it reappears in device manager
e) using TeraTerm, attempt to connect to the com-port.

Now things don't work any more -- TeraTerm can't see the com-port (even though it does appear in the device manager) Same problem with Putty.

I found that if, before step c) above, I first close the port from TeraTerm, things work as expected. (and I did disable USB power management).

Has anyone else experienced this? I still don't know if it's a Windows problem, or if the act of unplugging a Teensy with an active USB connection causes problems with the Teensy USB software stack?????

Greg

 

[Fuell]

Hi bigredbee, I know this is a very old thread, but I have the same problem. Did you find a way around this problem?

Best regards, René

 

[bigredbee]

I think this is "just the way it works". I've trained myself to always disconnect TeraTerm before powering down or unplugging the Teensy.

Greg

 

[Fuell]

Hi Greg,

Thanks for the feedback. I also work as you describe above.
When this problem occurs during a remote (TeamViewer) session on another PC, I can't disconnect the USB cable though.
I googled further and found that going to the Windows Device Manager and disable/enable the comport there works well.
This is an acceptable solution as long as we have nothing better.
If anyone has a solution that can be automated from software without too many admin rights etc. then please add this below...

Best regards, René