Port number > 100 not seen (was STM32 VCP driver not seen)
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#69 Port number > 100 not seen (was STM32 VCP driver not seen)
Hello there,
I am using RealTerm for a long time, but it doesnt sometimes pick up virtual com ports from certain drivers. For example, the STM32 VCP usb driver, that allows STM32 MCU devices connected through USB, be seen by the PC as serial ports. Tera term sees the COM port but it is not listed under available ports in Real Term program. Is it something that can be fixed? I would apreciate all help.
Recent versions (eg 3.0.0.29) have some new options at the bottom of the ports drop down
"Port from Registry" and "Exhaustive Search by Opening"
Please try both of these and see if it finds them, and report back.
Hi,
Where can I find this version? In files section most recent is 2.0.0.70.
Edit: I found it, but it still doesnt show, even FTDI ports.
Last edit: Lukasz 2016-01-07
RT finds ports by looking in registry at key
HKEY_LOCAL_MACHINE\HARDWARE\DEVICEMAP\SERIALCOMM
Serial comm devices are listed here (well when plugged in they are)
Have a look in here with regedit, and see if your port is listed.
However if the port is not found by exhaustive search it implies that on your system the ports are not being given an actual comport number.
Do you know the comport number of these vcps?
Can you open them using that number?
If not how are they named?
Does device manager show them as comports?
Last edit: Simon Bridger 2016-01-07
Yes they work, because I can open them in Terraterm and putty.
You have the system not me, and so you need to do the digging to answer these questions so we can get some idea of why RT does not find your specific ports:
Is the port in the registry at HKEY_LOCAL_MACHINE\HARDWARE\DEVICEMAP\SERIALCOMM
( when it is plugged in)?
Do you know the comport number of these vcps?
Can you open them by entering that com number in RT?
If not how are they named?
Does device manager show them as comports? if not are they visible in device manager when view->hidden is set?
You say "but it doesnt sometimes pick up virtual com ports from certain drivers". Do you mean that this specific STM32 device is discoverable today, but not tomorrow. Or is it never discoverable?
I have cheked what you asked for, have a look. This is the registry:
https://www.dropbox.com/s/xr79emp9whh4nmq/Zrzut%20ekranu%202016-01-08%2006.55.28.png?dl=0
The serial ports are listed. They are also listed in TerraTerm for example:
https://www.dropbox.com/s/pstfzh5wqordb9y/Zrzut%20ekranu%202016-01-08%2007.07.23.png?dl=0
But not in RealTerm:
https://www.dropbox.com/s/4f8cax6sv9eiy47/Zrzut%20ekranu%202016-01-08%2006.55.58.png?dl=0
The ports that are not visible in RealTerm are FTDI devices in this case.
Last edit: Lukasz 2016-01-08
I wonder if it something to do with the com# being >100?
If you try to open it by number ie 133, does it open and work OK?
Does it open by name \VCP1 ?
OK looks like there was MAXCOMPORT=100
Now 999
Try this exe: https://www.dropbox.com/s/uwci0lcucobdncr/realterm.exe?dl=0
Ticket moved from /p/realterm/feature-requests/39/
Can't be converted:
Now its visible, thank you :)!
BTW this link might help get find and remove the old orphan usb ports
https://learn.adafruit.com/how-to-find-hidden-com-ports/overview
You can also manually type a port number into the RealTerm 'Port' drop down box. Mine was 206, and I typed it in manually, which worked when 206 was not showing up as an option in the drop down.