Slow drive access

[Deniska]

Hi!

First of all thank you for developing this driver, as the DOS community is in real need of such software. Your mass storage driver works fine on my computer with an UHCI controller. I can plug and unplug as many flash drives and portable drives as I like without problems. However, the transfer speed is really slow, on the order of 25 Kb/s, while the speed of the Panasonic USBASPI mass storage driver is ~500-600 Kb/s. Is there a reason for this or am I likely to be doing something wrong?

Deniska

[Bret]

Try experimenting with the /X:# option. This controls how many sectors USBDRIVE will try to transfer at one time. Some drive and controller combinations cannot handle trying to send too many sectors at one, and you'll get lots of "Disk Not Ready" errors.

The default value that USBDRIVE uses for the # is 1, which is slow but very reliable. The maximum value you can use for the # is 64, which is supposedly as fast as any drive can go, but may not be reliable (depending on your hardware). You will just need to experiment until you find the best value to use.

I personally have three different computers and several different flash drives, and I've found the best value for me to use is 4. I have one flash drive (made by SanDIsk) that works fine at X:64, but the rest of them are unreliable at anything higher than 4. There is a sample table in the documentation (USBINTRO.DOC) that shows some experiments I did with different values for X.

[iw2evk]

Hi,
thsi is my experience with 6 usb stick of varius size and a digital
camera and 4 way self powered hub.

If the device can be recognized from drivers , setting x=1 or x=64
change dramaticaly the time of access .

If the device it's NOT recognized from drivers , setting X=1 or other
don't change any..

See my experience in forum :"usb rebel stick"...

Roberto iw2evk

Milan