egray@fthood.UUCP (12/07/86)
HELP! I just purchased a hard disk with an 'ST412' interface. It seems that my controller will accept only a 'ST506' drive. What is the difference in the interfaces? Is there modifications possible, or am I doomed to return the drive? The drive is a Seagate ST251, the computer is an AT&T Unix PC 7300 (with the controller built into the mother board. Emmet P. Gray US Army, HQ III Corps & Fort Hood ...!ihnp4!uiucuxc!fthood!egray Attn: AFZF-DE-ENV DEH, Environmental & Natural Resources Management Office Fort Hood, TX 76544-5057
rdr@inuxh.UUCP (12/10/86)
> > HELP! I just purchased a hard disk with an 'ST412' interface. It seems > that my controller will accept only a 'ST506' drive. What is the > difference in the interfaces? Is there modifications possible, or am I > doomed to return the drive? > > The drive is a Seagate ST251, the computer is an AT&T Unix PC 7300 (with > the controller built into the mother board. > There should be no problem there - I've done it before, though the specific drive and controller were different. What you can't do is put an ST506 drive on an ST412 controller. The difference between 506 and 412 is small - the 412 supports a "buffered seek" capability. This allows a controller to tell a drive to step the head many tracks at a time by sending all the step pulses very quickly - much faster than the drive can actually step. The 412 drive has enough smarts to buffer all the steps and move the head in one operation, rather than stopping at all the intermediate tracks. The reason you shouldn't have a problem is than your 506 controller simply won't send step pulses faster than the drive can step a track-at-a-time. The worst that happens is your controller won't move the head as fast as the drive could handle. Have you actually tried it? If so and it didn't work, then it's hard to say what your problem is, but I doubt it's the 506/412 mismatch. BTW, my experience was with a CMI 30meg drive for an AT, on a DTC5150BX controller in an AT&T 6300. Worked fine. Bob Rindfuss ...ihnp4!inuxh!rdr
grr@cbmvax.UUCP (12/11/86)
In article <7200001@fthood> egray@fthood.UUCP writes: > >HELP! I just purchased a hard disk with an 'ST412' interface. It seems >that my controller will accept only a 'ST506' drive. What is the >difference in the interfaces? Is there modifications possible, or am I >doomed to return the drive? > >The drive is a Seagate ST251, the computer is an AT&T Unix PC 7300 (with >the controller built into the mother board. >Emmet P. Gray The ST506 and ST412 are essentially the same interface. I would not expect you to have any problems with current production drives and interface boards. -- George Robbins - now working for, uucp: {ihnp4|seismo|rutgers}!cbmvax!grr but no way officially representing arpa: cbmvax!grr@seismo.css.GOV Commodore, Engineering Department fone: 215-431-9255 (only by moonlite)