by Problem with SCSI Future Domain TMC-850 / Seagate ST01/ST02 controller
with CD-ROM
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In July I posted a question about how to get my SCSI controller and
CD-ROM drive identified by Yggdrasil Summer'94 Linux, I have now solved
the problem as described below.
Following the Yggdrasil manual, I entered "linux tmc8xx=0xCA000,5" at the
boot: prompt. During the boot sequence my SCSI adaptor was identified as
a Seagate ST01/ST02 (it's a Future Domain TMC-850) - this confused me but
is apparently correct. However the TEAC-CD50 drive wasn't reliably
identified and in fact never worked.
I don't know whether the Yggdrasil Linux can be installed via DOS, but in
any case I purchased the InfoMagic CD's June '94 (these are very cheap),
and installed Slakware 2.0 Linux via my IDE drive. This process is
straight forward, however my SCSI adaptor was now not identified again.
Following advice from answers to my original comp.os.linux.help query I
edited the Makefile for the SCSI device drivers as follows -
in /usr/src/linux/drivers/scsi/Makefile I added -DCONTROLLER=FD -DIRQ=5
-DOVERRIDE=0xCA000 to the defines for seagate.o and re-compiled the Linux
kernel. The new kernel identified the SCSI adaptor correctly but still
had the same problems identifying the CD-ROM. I contacted Drew Eckhardt
(the author of the Seagate device driver) and he suggested that I edit
the seagate.c file (in the same directory as the Makefile above) to swap
two lines. The lines concerned set the CONTROL & DATA registers and are
adjacent in the code and are preceded by a comment that says they have
been reversed already. Anyway I reversed these two lines, re-compiled the
kernel and everything is now working perfectly.
I should stress that I'm a Linux beginner myself, but if anyone requires
further clarification of the above I'd be glad to assist (preferably via
EMail).
Howard C. Taylor (Southampton, England)