Path: utzoo!utgpu!attcan!uunet!cbmvax!eric From: eric@cbmvax.UUCP (Eric Cotton) Newsgroups: comp.sys.cbm Subject: Re: More on CBM D9060/D9090 IEEE-488 hard disks Keywords: D9090 D9060 PET IEEE Hard disk Message-ID: <5636@cbmvax.UUCP> Date: 6 Jan 89 15:41:03 GMT References: <29863@tut.cis.ohio-state.edu> Reply-To: eric@cbmvax.UUCP (Eric Cotton) Organization: Commodore Technology, West Chester, PA Lines: 42 In article <29863@tut.cis.ohio-state.edu> erd@tut.cis.ohio-state.edu (Ethan R. Dicks) writes: > >o Does anyone know the HDA (Head Disk Assembly) used in either drives? The > disk geometries are: > > D9060 4 heads, 153 cylinders, 32 sectors, 256 bytes per sector. > D9090 6 heads, 153 cylinders, 32 sectors, 256 bytes per sector. Correct. The D9060 has a Tandon 602S drive, the 9090 a 603S. > > With current standard controllers (MFM), the capacity would be: > 4 * 153 * 17 * 512 = 5,326,848 bytes or 5.2 Mb > 6 * 153 * 17 * 512 = 7,990,272 bytes or 7.8 Mb > > With the Commodore controller, the capacities are listed as 4.98 Mb > and 7.47 Mb. The spec I have lists 5.01 Mb and 7.52 Mb formatted, including directory. > (There is a software imposed limit of 32 sectors/track in the directory > sector format of CBM disk drives) > > >o Does anyone have any infomation on DOS 3.0, used with these drives? > (One undocumented bit is the format of the bad block tables) I must have the info around here somewhere. If I find anything I pass it along. >o Must these drives be formatted at the factory? Can a program be > downloaded via M-W commands and run via the M-E command to do a low level > format? (I am thinking of building my own hard drive, but have no idea > how to format it) I don't belive they need be formatted at the factory? I recall formatting a couple myself many years ago... -- Eric Cotton Commodore-Amiga (215) 431-9100 1200 Wilson Drive {uunet|pyramid|rutgers}!cbmvax!eric West Chester, PA 19380 "I don't find this stuff amusing anymore."