View Full Version : Wd1003-cmd

August 21st, 2014, 11:34 AM
I am looking for information on a WD1003-CMD hard disk controller. It is used in a Commodore 900 system I am trying to revive, and is supposed to control a 20MB MFM hard disk. It appears that the hard disk is not formatted, so I am looking for a way to format it.

A Google and Ebay search brought me a bunch of PC ISA controllers like WD1003-WA2, WD1003-RA2 and so on. But the WD1003-CMD is not an ISA card but has some custom DMA interface to the Z8000 bus of the Commodore. So I am not sure how to format the disk (the Commodore does not come with any software to do so).

Would the various PC WD1003-xxx controllers use the same low-level format as the WD1003-CMD? The common "WD1003" prefix makes me suppose that it is so, but I would like to gather as much information as possible before I start buying and assembling a PC/AT system just to format a disk.

August 23rd, 2014, 09:28 AM
I don't know. FWIW, the WD1003-WA2 User's Guide (-019) says: (winchester drives) "requires execution of low level formatting. Use of the IBM Advanced Diagnostic (or similar program for IBM compatibles) is necessary since these controllers contain no on-board Basic Input/Output System (BIOS)ROM."