[ct-user] USB memory sticks (Thumb Drives) Under DOS

kd4d at comcast.net kd4d at comcast.net
Thu Feb 3 20:23:40 EST 2005

Good afternoon, all:

I have a computer which, when I boot DOS, does not see the USB
stick plugged into the computer.  Thanks to Patrick, PA5AEI, I
now have the USB stick running under DOS.  I'm actually using
FreeDOS for this experiment.

The key is two device drivers:  USBASPI.SYS and ASPIDISK.SYS.

Along with the proper config.sys file, these detect my USB stick
and DOS makes it C: or D:!  Note:  I had to let DOS start
booting, put a pause (using the MENU directive) in config.sys,
and plug the USB stick after DOS starts.

The critical parts of the config.sys file are:

device=usbaspi.sys /v /slow

This works on two of my computers with USB slots and which
did not work with DOS without these drivers.

I got the two ".sys" files from a Puppy Linux startup disk image.

and used the VFD (Virtual Floppy Driver) to open the image.  These
files are readily available from the web.  You can see


I didn't know this was even possible!

Thanks, Patrick.


Mark, KD4D

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