USB flash memory write caching

  • Thread starter Thread starter DPM
  • Start date Start date
D

DPM

I've built 2 images: one on SP2/FP2007 and the other on
SP2/FP2007/UpdateRollup1. First runs on a AMD MB, second on an Intel.

Now: my application writes a few files to a USB flash drive. On the first
image when the flash LED stops blinking I can remove it, plug it into a PC
and my files are there. On the second, after the initial flashing stops if
I pull it out - no files. If I leave it in, 20-30 seconds later there's
more LED activity, then if I pull it my files are there.

So: was write caching turned on in UR1, or is this a function of my
hardware? Are there registry entries that control this?

If someone has any insight I'd be grateful.

Thanks,
Dean
 
Dean,
in device manager select your USB device, right click Properties, open tab
Policies and you see the
writing cache status. Default for removable device is OFF.
If your image is unable to open device manager search the key
"UserRemovalPolicy" for your device
using regedit.
Values I found are 3 No cache 2 cache on.
The full path should be:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\<XXX>\<YYY>\<ZZZ>\DeviceParameters\Classpnp
X Y and Z are ID for your device.
Regards
Raffaele
 
Problem solved: I inadvertently added a USB Boot component to my image, and
doing so apparently changed the way XP treated USB drives. Removing the
component solved my problem.

Thanks,
Dean
 
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