USB cable disconnect/reconnect, but via software?

  • Thread starter Thread starter az
  • Start date Start date
A

az

Hello to all,
I've bought a CF/etc.. card reader, which sits into a floppy drive slot.
Really nice to have an internal card reader, I thought. But then I realized
that the fact that it is internal has put me in big trouble, since when I
need to remove the CF card, I do it in the safe way, i.e. clicking on the
tray icon "Stop USB Mass Storage Device".
Well, then the only way to get another card recognized is either a reboot
or disconnecting and reconnecting the physical cable. The latter is not
possible unless I open and close the PC each time.. the former is not
possible either, since I work with a lot of applications opened and the
rare times I remove power to the PC I put it in hybernation before. For
me rebooting each time I need to change CF would be even more impractical
than having to open and close the PC to disconnect/reconnect the cable.
Also, I got twice the problem, since (because I reboot very rarely) I also
have a USB to IDE interface, handy because it's hot plug, and I also got
now an internal deck I'd like to use for HD removability with hot plug.

I'm sincerely astonished that in 2006 one HAS TO unplug and replug a cable
in order to get recognized again a device.

Is there any software solution to my problem? Even if complex to use.

Thanks a lot,
A.Z.
 
Hello to all,
I've bought a CF/etc.. card reader, which sits into a floppy drive slot.
Really nice to have an internal card reader, I thought. But then I realized
that the fact that it is internal has put me in big trouble, since when I
need to remove the CF card, I do it in the safe way, i.e. clicking on the
tray icon "Stop USB Mass Storage Device".
Well, then the only way to get another card recognized is either a reboot
or disconnecting and reconnecting the physical cable. The latter is not
possible unless I open and close the PC each time.. the former is not
possible either, since I work with a lot of applications opened and the
rare times I remove power to the PC I put it in hybernation before. For
me rebooting each time I need to change CF would be even more impractical
than having to open and close the PC to disconnect/reconnect the cable.
Also, I got twice the problem, since (because I reboot very rarely) I also
have a USB to IDE interface, handy because it's hot plug, and I also got
now an internal deck I'd like to use for HD removability with hot plug.

I'm sincerely astonished that in 2006 one HAS TO unplug and replug a cable
in order to get recognized again a device.

Is there any software solution to my problem? Even if complex to use.

Thanks a lot,
A.Z.
Click to expand...

Rather than clicking "Stop USB Mass Storage Device", you
can probably use the disable/enable function of devcon.exe.
I haven't tested this much so you may need to try it for
yourself with your compact flash device. You can get
devcon.exe from here:
http://support.microsoft.com/default.aspx?scid=kb;EN-US;Q311272
 
In
Hello to all,
I've bought a CF/etc.. card reader, which sits into a floppy drive
slot. Really nice to have an internal card reader, I thought. But
then I realized that the fact that it is internal has put me in big
trouble, since when I need to remove the CF card, I do it in the safe
way, i.e. clicking on the tray icon "Stop USB Mass Storage Device".
Click to expand...

I don't do that just to remove a card. I just make sure the light isn't
flashing. The card is not a device, like a USB flash memory thingy is.
I THINK I'm right about this.
Well, then the only way to get another card recognized is either a
reboot or disconnecting and reconnecting the physical cable.
Click to expand...

How about using the "discover new hardware" function in the control
panel?.......NO! just tried it. It will discover the device but it has a
yellow exclamation point. Now I have to reboot :(
I'm sincerely astonished that in 2006 one HAS TO unplug and replug a
cable in order to get recognized again a device.
Click to expand...

You are right. I am amazed too. Always thought "discover new HW would work.
I wonder what's different between a reboot and a "look for new hardware..."

Any other opinions on the safety of just pulling the CF card w/o "ejecting"
the USB device? I'm curious.
 
In

I don't do that just to remove a card. I just make sure the light isn't
flashing. The card is not a device, like a USB flash memory thingy is.
I THINK I'm right about this.


How about using the "discover new hardware" function in the control
panel?.......NO! just tried it. It will discover the device but it has a
yellow exclamation point. Now I have to reboot :(


You are right. I am amazed too. Always thought "discover new HW would work.
I wonder what's different between a reboot and a "look for new hardware..."

Any other opinions on the safety of just pulling the CF card w/o "ejecting"
the USB device? I'm curious.
Click to expand...

I now also have to pull the plug and re-connect. This is something that just
happened to me some 3-4 months ago.
Prior to that I booted the computer and the card reader, connected to the hub
was ready to work and the icon for remove was ready in the taskbar.
I can avoid that by using a direct connection to the front or rear of the
computer without going through the hub. I suspect it was an update from MS that
caused the trouble.

Borge in sunny Perth, Australia
 
since when I
need to remove the CF card, I do it in the safe way, i.e. clicking on the
tray icon "Stop USB Mass Storage Device".
Click to expand...

You don't need to stop the drive in order to eject the media. In
Explorer, right-click the drive and chose "eject". That will flush the
write cache and prepare for safe removal of the media.

Also, external USB disks are not write-cached by default, so if you
wait for the light to indicate no activity, you are essentially safe.
 
Robert said:
You don't need to stop the drive in order to eject the media. In
Explorer, right-click the drive and chose "eject". That will flush the
write cache and prepare for safe removal of the media.
Click to expand...

Yes, but as far as I've tested admin previleges are
required for that.
Also, external USB disks are not write-cached by default, so if you
wait for the light to indicate no activity, you are essentially safe.
Click to expand...

Sure? I think that is true for XP but under Windows 2000
USB drives have a write cache.


Greetings from Germany

Uwe
 
Yes, but as far as I've tested admin previleges are
required for that.
Click to expand...

I did not know that. I always work with admin rights, so I have never
run across the problem. I just tested, and I can confirm your
experience. The error message is quite obscure as well.

For fun, I tried setting the local security policy to allow "plain"
users to eject NTFS media. That actually worked, even though my memory
card is formatted with FAT. This has to be a bug?
Sure? I think that is true for XP but under Windows 2000
USB drives have a write cache.
Click to expand...

Not THAT sure :-)

I just tested with a SmartMedia card reader.. In this test, the "Write
cache enabled" is even grayed out so it cannot be enabled at all.

I tested this in a VMware environment, which may cause different
behavior.
 
Robert said:
I did not know that. I always work with admin rights, so I have never
run across the problem. I just tested, and I can confirm your
experience. The error message is quite obscure as well.
Click to expand...

Yes, the MS guys seems to work as admins too so they have
never seen it...
For fun, I tried setting the local security policy to allow "plain"
users to eject NTFS media. That actually worked, even though my memory
card is formatted with FAT. This has to be a bug?
Click to expand...

Wow, that's interesting. I've seen this behaviour as irrevocably
fact.
Not THAT sure :-)

I just tested with a SmartMedia card reader.. In this test, the "Write
cache enabled" is even grayed out so it cannot be enabled at all.
Click to expand...

These option doesn't seem to mean that much. A simple test shows
if there is a write cache or not: Goto \WINNT\INF, sort by size,
mark the 30 smallest files and drag them to the USB drive. If you
can see how every single file is written while the lamp on the drive
is hecitc blinking then there is no cache.
If you get a short 'rush' and the lamp blinks after the Explorer
reported finish, then there is a write cache.


Greetings from Germany

Uwe
 
If you
can see how every single file is written while the lamp on the drive
is hecitc blinking then there is no cache.
If you get a short 'rush' and the lamp blinks after the Explorer
reported finish, then there is a write cache.
Click to expand...

I just tested. The copy was quite slow, and the light would flicker
all the time while copying. No light activity visible after the copy
was finished.

Whether or not there is a write cache in use could, of course, be
determined by the driver for the device. The driver could even
implement its own caching.

I guess the conclusion is that you should eject your media unless you
are certain there is no write cache anywhere.
 
Robert said:
I just tested. The copy was quite slow, and the light would flicker
all the time while copying. No light activity visible after the copy
was finished.
Click to expand...

Strange. Under W2K I always had a write cache using the
W2K generic drivers.
I guess the conclusion is that you should eject your media unless you
are certain there is no write cache anywhere.
Click to expand...

Yep :-)


Greetings from Germany

Uwe
 
Back
Top