Path: utzoo!attcan!uunet!husc6!tut.cis.ohio-state.edu!erd From: erd@tut.cis.ohio-state.edu (Ethan R. Dicks) Newsgroups: comp.sys.cbm Subject: More on CBM D9060/D9090 IEEE-488 hard disks Keywords: D9090 D9060 PET IEEE Hard disk Message-ID: <29863@tut.cis.ohio-state.edu> Date: 21 Dec 88 04:08:18 GMT Organization: The Ohio State University Dept of Computer and Information Science Lines: 54 I have already gotten two mail replies to my first message, one a plea for any information I got, so I am going to refine my inquiries. o Does anyone know where to get ahold of either a D9060 or a D9090, working or not? 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. 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. (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) 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) If I can not get a CBM manufactured drive, I am considering trying to make an IEEE <-> PC BUS/PC drive card adapter, whereby you plug an IBM PC/XT Western Digital WX-1 interface to an ST-506 style drive, and an IEEE controller onto the WX-1. This scheme avoids most of the work with the analog circuits for about $60. I would *MUCH RATHER* buy one than build one... I have better things to do with my time than build single board drive interface. All above statistical information is from the "Disk System User Reference Guide" (1980) Commodore Business Machines. Thanks, -ethan -- Ethan R. Dicks | ###### This signifies that the poster is a member in Software Results Corp| ## good sitting of Inertia House: Bodies at rest. 2887 Silver Drive | ## Columbus OH 43211 | ###### "You get it, you're closer.