An odyssey with an 8bit Seagate SCSI controller ...
Tuesday, March 25, 2014, 10:40 PM
Posted by Administrator
Not funny, but instructive.
I've tried to add a bigger SCSI drive to my PC/XT system, which uses a Seagate ST-02 controller. At the moment, it runs well with a small Conner 3040 HDD (= 40MB), but I liked to have a bit more HDD capacity.
So I obtained a Seagate ST51080N, which has in fact 1080MB capacity, but still a 50 pin interface. Unfortunately I was able to read some messages about
Seagate ST-02, which describes a limit for bigger HDDs - but not clearly described what limit, but it seems to be related with the older ROM version of the controller.
So I decided to upgrade the BIOS from 3.0 to 3.32, found at
http://ftp.mpoli.fi/hardware/ROM/SEAGATE/ ... but someone made a mistake describing that ROM.
It was NOT Seagate SCSI BIOS V3.32, but SyDOS SCSI BIOS V3.35 (but still based on Seagate's SCSI ST-01/ST-02 BIOS). It had some additions for Sygate's EZ135, which sounds nice, but was not helpful for getting bigger drives working properly.
I ended with using the Conner 3040 again, which works with the old BIOS version as well as with the new BIOS version.
Conclusion: Don't trust on file descriptions, nor on user messages about compatibility of old hardware. Seagate's ST-01/ST-02 is only able to operate with drives less than 1024MB. Nothing else.