Dangerous Prototypes Open Source Hardware

PIC USB --> RS-232 emulation driver removal tool?

May 28, 2010, 02:22:34 am

I noticed when I installed 0.4v of the PIC firmware and installed the new driver the OBLS was assigned to COM10 where it was previously COM9.  I could not assign it to COM9 because device manage said it was in use.  I have had this issues with FTDI devices before once you connect enough FTDI devices over time all you keep getting progressively higher COM port assignments.  This can be easily fixed on FTDI chips buy running their driver removal tool.  Does pic off a RS-232 USB driver removal tool also?

Re: PIC USB --> RS-232 emulation driver removal tool?

Reply #1 – May 28, 2010, 10:12:25 am

You said COM, so I'm assuming your OS is Windows. I am able to go into the device manager and select an '(in use)' COM port and reassign the OLS. It gives a warning, but it seems to work fine. When you're done, do 'action->scan for hardware changes' to see if the change worked.

Re: PIC USB --> RS-232 emulation driver removal tool?

Reply #2 – June 15, 2010, 05:44:10 pm

I figured out how to remove the unused PIC COM assignments in windows the trick is to get device manager to show disconnected devices.  Here's how.

1) Open command prompt as administrator
2) Type set devmgr_show_nonpresent_devices=1 and press enter
3) Type start devmgmt.msc and press enter or go into device manager in windows
4) In device manger select Show hidden devices from the view menu.
5) Expand Ports (COM & LPT) and right click -> uninstall any unused COMs, select remove driver check box if available.

Re: PIC USB --> RS-232 emulation driver removal tool?

Reply #3 – June 15, 2010, 07:54:54 pm

Good one ... reminded me to clean up all the useless assigned COM ports on my system!

The other way (that will make the setting that allows you to see unused devices persistent) is:

1. right click My Computer and select Properties
2. in Properties select Advanced and click the Environment Variables button
3. click on New under System Variables
4. for Variable Name enter devmgr_show_nonpresent_devices, for Value 1, klick Ok twice

This assigns the system variable devmgr_show_nonpresent_devices the value 1 and makes the setting persistent so it's always available, even after a reboot/restart. To see/delete/modify unused devices open Device Manager (right click My Computer --> Properties --> Hardware -> Device Manager) and follow steps 4 and 5 as described by LukeS.

Re: PIC USB --> RS-232 emulation driver removal tool?

Reply #4 – June 20, 2010, 07:47:11 pm

Hi,

Just a good hint for guys with problems on USB installation a good tool http://www.nirsoft.net/utils/usbdeview.zip is avalailable to see all driver installed to disable/enable or uninstall them.
It could be also very useful to cleanup/uninstall unused old USB device registered ...

Best Regards

TitanMKD