Suggestion : Diagnostic hardware to be supplied with every AXE027
- Thread starter Buzby
- Start date
Hi Jim,
Windows is terrible in the way it enumerates and allocate Virtual Com ports. Here's what you do and what has worked well for me.
Here's what you do.....
1. Power off PC
2. Unplug all unnecessary USB Devices including AXE027
3. Power up PC
4. Open device manager
5. Plug in Axe027
6. Device Manager should show AX027 under "Ports Com & LPT
7. Ignore Com Port Number
8. Double click on Axe027 > Port Setting > Advanced
9. At the top under "Port Number" click the down arrow to view the ports
10. Use the slider to see all the ports that are marked "in use"
11. These "in use" ports are really not "in use" ....
12. Go to the highest "in use" port then click OK.
13. Ignore the warning message. Click Yes. Devic manager will re-enmerate when it is done ....
14. Click on Advanced again.
15. Goto the highest "in use" port then click OK.
16. Ignore the warning message. Click Yes. Device manager will enmerate .....
17. Keep repeating 12 - 16 until you get to com 4. Leave the AX027 on Com4
Now when you open device manager and select the AX027 > Port settings > Advanced > and open Port Number, all of the bogus "in use" ports should be gone and the AXE027 should be working reliably on Com 4.
Now reconnect any other USB devices that your system uses.
Windows is terrible in the way it enumerates and allocate Virtual Com ports. Here's what you do and what has worked well for me.
Here's what you do.....
1. Power off PC
2. Unplug all unnecessary USB Devices including AXE027
3. Power up PC
4. Open device manager
5. Plug in Axe027
6. Device Manager should show AX027 under "Ports Com & LPT
7. Ignore Com Port Number
8. Double click on Axe027 > Port Setting > Advanced
9. At the top under "Port Number" click the down arrow to view the ports
10. Use the slider to see all the ports that are marked "in use"
11. These "in use" ports are really not "in use" ....
12. Go to the highest "in use" port then click OK.
13. Ignore the warning message. Click Yes. Devic manager will re-enmerate when it is done ....
14. Click on Advanced again.
15. Goto the highest "in use" port then click OK.
16. Ignore the warning message. Click Yes. Device manager will enmerate .....
17. Keep repeating 12 - 16 until you get to com 4. Leave the AX027 on Com4
Now when you open device manager and select the AX027 > Port settings > Advanced > and open Port Number, all of the bogus "in use" ports should be gone and the AXE027 should be working reliably on Com 4.
Now reconnect any other USB devices that your system uses.
Hi Goeytex,
I'm certainly no Windows expert, but that procedure seems a little drastic. Is one likely to have to search around for some ancient Install disc in a few months time when one plugs in an occasionally-used USB dongle? Or does Windows keep a complete set of previously-used "INF" files, or whatever are required to re-install USB devices?
Firstly, it doesn't seem to be essential to work right down through the list of COM ports, it appears to be possible just to "hijack" any one of the "in use" ports, e.g. 16 or below to use the PE (but I've only just tried this for the first time).
However, a Google found this rather interesting Microsoft support document. It allows you to see what Windows thinks is using all the COM ports. You may well find a particular device which you know you will never use again, or which appears to be hogging an excessive number of Ports, that you can delete with a right-click.
Cheers, Alan.
I'm certainly no Windows expert, but that procedure seems a little drastic. Is one likely to have to search around for some ancient Install disc in a few months time when one plugs in an occasionally-used USB dongle? Or does Windows keep a complete set of previously-used "INF" files, or whatever are required to re-install USB devices?
Firstly, it doesn't seem to be essential to work right down through the list of COM ports, it appears to be possible just to "hijack" any one of the "in use" ports, e.g. 16 or below to use the PE (but I've only just tried this for the first time).
However, a Google found this rather interesting Microsoft support document. It allows you to see what Windows thinks is using all the COM ports. You may well find a particular device which you know you will never use again, or which appears to be hogging an excessive number of Ports, that you can delete with a right-click.
Cheers, Alan.
The procedure I posted is a lot less "drastic" than going into the registry and whacking the appropriate registry keys.
And certainly not as "drastic" as a Windows reinstall.
My "drastic" procedure will take less than 5 minutes and will do no harm.
Goey
Addendum:
I purposely created some VCP entries by plugging in multiple FTDI,AXE027, CP2102, Prolific,and CH340 adapters into all of the different USB ports on my Laptop. I kept swapping them around and plugging them into different USB slots until there were created "in use" virtual com ports up to com 22 even when these devices were removed. Then I ran the Microsoft procedure posted above by Alan.
All of these "in use" but not really used devices showed up in device manager as hidden devices. It was then a simple matter of uninstalling them via Device Manager.
So this looks like another and likely better option than the procedure that I suggested.
And certainly not as "drastic" as a Windows reinstall.
My "drastic" procedure will take less than 5 minutes and will do no harm.
Goey
Addendum:
I purposely created some VCP entries by plugging in multiple FTDI,AXE027, CP2102, Prolific,and CH340 adapters into all of the different USB ports on my Laptop. I kept swapping them around and plugging them into different USB slots until there were created "in use" virtual com ports up to com 22 even when these devices were removed. Then I ran the Microsoft procedure posted above by Alan.
All of these "in use" but not really used devices showed up in device manager as hidden devices. It was then a simple matter of uninstalling them via Device Manager.
So this looks like another and likely better option than the procedure that I suggested.
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One thing I found with Windows XP is that, even when all phantom / no longer used ports were removed, adding a port still gave it a high number. It may have been the way I was using Device Manager, and Goeytex's instructions in post #42 may fix that, but there's a registry entry that is a binary bit map of all port numbers previously allocated which wasn't being reset and had to be updated manually ...
HKLM/System/CurrentControlSet/Control/COM Name Arbiter
HKLM/System/CurrentControlSet/Control/COM Name Arbiter
I always had persistent problems with XP and USB devices. Although the AXE027 was usually trouble free, other USB devices such as flash memory cards would work for a while, and then would just not be recognised (nothing wrong with the memory cards BTW).
A re-image of XP would cure it, for a while.
I think that depends on the quality of the USB code in the BIOS on the motherboard. My Dell laptop consistently uses the same ports for the various USB devices I have (thumb drives, AXE027, Belken USB-serial for weather station, etc). I have a desktop with a "brand name" motherboard that sometimes simply drops the connection to a USB wireless network device, although it works OK with USB drives.