v1b@mhuxi.UUCP (davis) (03/11/86)
Does anyone know how to do a physical format on the AT&T PC6300 hard disk? I would like to use the hard disk in another pc (Leading Edge PC) but I have been unable to get the Leading Edge to acknowledge the existance of the hard disk. I thought that a physical format run on the Leading Edge might fix that. Thanks in advance. Vern Bradner (ihnp4!mhuxi!v1b)
rdr@inuxh.UUCP (Robert Rindfuss) (03/14/86)
> Does anyone know how to do a physical format on the AT&T PC6300 hard disk? > I would like to use the hard disk in another pc (Leading Edge PC) but > I have been unable to get the Leading Edge to acknowledge the existance > of the hard disk. I thought that a physical format run on the > Leading Edge might fix that. > > Thanks in advance. > > Vern Bradner (ihnp4!mhuxi!v1b) Brad- Try the following BASIC program. It stuffs the right values in the DTC controller's registers and tells the controller to do the format. The program inself runs in less than a second, but the drive will be busy awhile. The program was from a PC Tech Journal some time back, and also works on IBMs. Bob Rindfuss AT&T Consumer Products ihnp4!inuxc!inuxh!rdr 70 out &h322, &h1 'get adapters attention 80 out &h320, &h4 '(B0) class = 0; opcode = fmt drv 90 out &h320, &h0 '(B1) drive 0 (c:), head 0 100 '[use &H20 for drive 1 (d:)] 110 out &h320, &h0 '(B2 & B3) start @ cylinder 0 120 out &h320, &h0 'sector 0 and format entire disk 130 out &h320, &h6 '(B4) interleave factor = 6 140 out &h320, &h0 '(B5) reread on ECC, default type 150 end
gemini@homxb.UUCP (Rick Richardson) (03/14/86)
... [Context: Simple format program given in BASIC] I would not ever recommend doing a low level format such as what was given. Those sectors are going to be used for a very long time. You DO NOT want to find out about marginal sectors AFTER they have been filled with valuable data. PC-DOS won't find these when it does the high-level format, either. The only way I'll trust my data is with a formatting program which not only does the format, but then spends many passes reading and verifying the entire surface of the disk. When a bad sector is found, the entire track should be reformatted with "BAD SECTOR ID" indicators, so that it will not be used by PC-DOS or any other operating system. Many times I've seen sectors verify for 3 or 4 surface passes, then fail on the next pass. Any format program that doesn't do this, isn't worth using on my data. Do you feel lucky? It's easy to tell what kind of format you're getting. If it only took 5 minutes to format your 10/20MB disk, you may be in for an untimely surprise. If it took more like an hour you can sleep a little sounder. Rick Richardson, PC Research, Inc. (201) 922-1134 ..!ihnp4!houxm!castor!{rer,pcrat!rer} <--Replies to here, not to homxb!!!
dw@rocksvax.UUCP (Don Wegeng) (03/17/86)
In article <1323@homxb.UUCP> gemini@homxb.UUCP (Rick Richardson) writes: >When a bad sector is >found, the entire track should be reformatted with "BAD SECTOR ID" >indicators, so that it will not be used by PC-DOS or any other >operating system. Why the entire track? What evdience do you have that other sectors in that particular track are bad or going to go bad? Just curious... /Don -- Some things can never be spoken, Some things cannot be pronounced... arpa: Wegeng.Henr@Xerox.COM uucp: {{decvax,harvard,seismo}!rochester,ihnp4,princeton}!rocksvax!dw
gemini@homxb.UUCP (Rick Richardson) (03/18/86)
Don Wegeng writes: > In article <1323@homxb.UUCP> gemini@homxb.UUCP (Rick Richardson) writes: > >When a bad sector is > >found, the entire track should be reformatted with "BAD SECTOR ID" > >indicators, so that it will not be used by PC-DOS or any other > >operating system. > Why the entire track? What evdience do you have that other sectors in > that particular track are bad or going to go bad? Just curious... Two reasons, really. The first is for performance. The second reason is more superstitious than anything else. I figure that defects come from three possible sources: uneven media, scratches during manufacture, or unwanted head landings. Since I can't be sure what the cause was, I assume it was the worst case - the head landing. If it landed on one sector of a track, it likely did some damage to other sectors. I don't trust them. Rick Richardson, PC Research, Inc. (201) 922-1134 ..!ihnp4!houxm!castor!{rer,pcrat!rer} <--Replies to here, not to homxb!!!