Interested for Conner CP30540 and IBM DSAS-3360 1/3 height 3.5" 364MB
PM sent.
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I thought (correct me if im wrong) there is no theoretical limit on old 50 pin scsi drives, the whole point of scsi was to hand off the management of the media to the drive itself avoiding poorly written or old PC bios limitations.
If i remember correctly IDE reports the actual layout of the drive sectors - heads - etc to make a capacity a minefield of issues but with scsi just the drive capacity is given which can be partitioned without the headache of compatibility issues. ??
the reason scsi seems to be more expensive. ???
SCSI was more expensive than ATA/ATAPI/(E)IDE primarily because it was a full, multi-target type (DASD, WORM, CD-ROM/-R/-W, SCSI HBA, Scanner, Library etc.),with potential subordinate Logical Unit Numbers [LUNs] per Physical Unit Number [PUN], and various other features being indicated/negotiated/controlled implementation. In other words a much more complex "bus" and related protocol implementation. If you wish to do your head in, follow this example Seagate SCSI-2/SCSI-3 drive specification changes PDF link:
https://www.seagate.com/support/disc/manuals/scsi/38479h.pdf
and that merely covers SCSI-2 and SCSI-3 for DASD Type devices. There are multiple bus speed increase specification changes (Ultra, Ultra2, Ultra160, Ultra320), but SCSI and EIDE have always tried to ensure downwards compatibility.
SCSI (C)BIOS implementation did go through some growth "pains" as drive capacities grew and grew and the CHS to LBA address translations fell into the odd hole along the way (1GB, 4GB and 8GB boundaries), before the Enhanced BIOS Interface became standardised.
Even now, the LBA count field size is having to be catered for as its length grows from 24-bit (8GB), to 32-bit (2TB) to 48-bit (128PetaB) assuming 512-byte sectors/blocks (further complicated by 4096-byte sectors/blocks). The same applies to EIDE drives of large capacities.