Claus-Justus Heine (claus@math1.rwth-aachen.de)
13 Sep 1998 16:50:26 +0200
> This is a mainboard issue since the board has something like three different
> bus speeds (CPU, PCI and ISA). The PCI <=> ISA bridge on some mainboards
> is known to flakey when doing 32 bit IO. What happens is that the correct
> amount of data is transfered but some of the bytes are replicated and overwrite
> other bytes. eg:
>
> Drive ParPort ISA Bus PCI Bus
> ABCD => ABCD => ABCD => ABBD
Also: Aha!
This would explain some problems I experienced with an Iomega Ditto
3200 floppy tape drive. However, it was the other way round, readind
with 32bit IO worked fine, but when writing to the floppy tape drive
there were CRC mismatches between the host and the external floppy
tape drive.
The ftape driver works around by silently switching back to 16 bit IO
when it detects such an error.
Claus
-- Claus-Justus Heine heine@math1.rwth-aachen.de http://www.math1.rwth-aachen.de/~heine/PGP Public Key: http://www.math1.rwth-aachen.de/~heine/claus-public-key.asc
Ftape - the Linux Floppy Tape Project WWW : http://www.math1.rwth-aachen.de/~heine/ftape/ Mailing-list: linux-tape@vger.rutgers.edu
-- To unsubscribe, send mail to: linux-parport-request@torque.net -- -- with the single word "unsubscribe" in the body of the message. --
This archive was generated by hypermail 2.0b3 on Wed 30 Dec 1998 - 10:18:17 EST