USB redetection after hibernation

**Goddy** · 12-05-2007, 09:24 AM

Hi,

I searched all over the forum but couldn't find anything regarding this issue.

The problem I have is since a few weeks when my carpc is getting back from hibernation it is redetecting / reinitializing all usb devices connected to the usb hub. I have the hub in the front with a usb radio, gps and sometimes usb stick (2GB). So everytime I resume from hibernation MapMonkey cannot find the GPS device (Comm port doesn't exist) and I have to reconnect manually in MapMonkey in order to make it work.
When I listen to the radio or play mp3s from the usb stick and go to hibernate -> resume it crashed because the device isn't there. After hibernation I can hear the USB detection sound going crazy (disconnect / connect sound like 4 times in a row).

I never had this problem, but I think it occurred after I reattached the USB cable in the wrong port (I had to reset the comport for the gps device) and played around with power saving for USB in the windows hardware section.

Now I tried everything, reattaching it to all other available ports, check/uncheck 'This device can start PC ...', hard restarts etc.

What do I need to do to get rid of this problem?

THANKS!

**scotty562** · 12-05-2007, 10:05 AM

I feel your pain. I got around the problem with a band-aid. I just lowered the boot up time as far as I could get it to go. ~30 seconds isn't too bad. Some guys have gotten their setups down to 15 seconds with flash cards though.

**Machinehead** · 12-05-2007, 10:22 AM

I would recommend looking into Devcon. It allows you to disconnect and reconnect USB devices automatically. There's a really well written and easy to follow FAQ in The FAQ Emporium.

**v8 scimitar** · 12-05-2007, 12:34 PM

Devcon is your friend http://www.mp3car.com/vbulletin/faq-...de-devcon.html

**Goddy** · 12-06-2007, 01:13 AM

Well, the thing is, I don't want it to disconnect / connect automaticly... because that is exactly what it is doing and giving me these problems. I just want it to get back smoothly from hibernation like it always did.

My boot time is already 15 seconds or something from hibernation and nothing I can do to speed it up.

**Machinehead** · 12-06-2007, 08:44 AM

Well, based on what you've written in your first post, your system isn't properly re-initializing your usb devices when it comes out of hibernation.

That's what devcon does.

**v8 scimitar** · 12-06-2007, 12:02 PM

I am with machinehead. I think your missing the point and all I can say is try it and see how you get on. You wont even know it has disconnected, it is just as if it was working properly.

**judoGTI** · 12-06-2007, 03:17 PM

Yep, just do a devcon restart for the ones that causing you issue after resume and it will make you very giddy and happy.

**Goddy** · 12-07-2007, 04:45 AM

Ok, I should give it a shot

But after I struggled with the usb ports I can't remember the last two times that I had the problem. I hope it's gone, but if not, I will try Devcon.

Thanks

**andyman** · 12-07-2007, 12:14 PM

I tried the devcon thing with no avail. (devcon hell).
I was daisy chaining USB hubs so naturally I was having issues.
My issue was at restart the usb devices all came back as some as unknown due to power issues.
I used a 12 volt adapter (cig adapter with usb power out).
What I did was made sure the aux power to the hubs came on before boot up and powered off after shutdown using delay relay circuits.
I had to also use diodes in line with the hub I powered externally (power wire only) to prevent back feeding power back to the other usb hubs.
I needed the extra power on one of my power hungry hubs. The diode kept the power in this one hub for it's self.

hope this helps.
I don't hibernate. I can startup in 35 seconds.
good luck