Formatting disk on rt11

Well, in *this* particular case, Mentec arranged for Andromeda to give me a SCDC controller with some SCSI drives and 5.25" and 3.5" floppies, and that's the reason why the Andromeda is supported for this operation under RT-11 5.7 :-). Not necessarily. I just hooked a true DEC RX50 to my SCDC, configured it, and it still lets me do a RX50 format: SCDC User Service Port V3.06 B Configure controller HARDWARE JUMPERS D Display/define physical DRIVE PARAMETERS A Assign logical DU/MU UNITS C Configure controller SOFTWARE OPTIONS E Exercise a SCSI DISK drive F FORMAT a DISK drive P RESET controller and EXIT ? d SCSI or Floppy (S or F)? f Floppy drive number (0 or 1)? 0 Floppy drive 0: 800 blocks Floppy drive types: 76 3.5" 80 track DS 134 5.25" 80 track DS 420 DEC RX50 dual drive Floppy drive type (76, 134, or 420) [134]? 420 SCSI or Floppy (S or F)? SAVE CHANGES- Are you sure (Y or N) [N]? y SCDC User Service Port V3.06 B Configure controller HARDWARE JUMPERS D Display/define physical DRIVE PARAMETERS A Assign logical DU/MU UNITS C Configure controller SOFTWARE OPTIONS E Exercise a SCSI DISK drive F FORMAT a DISK drive P RESET controller and EXIT ? f SCSI or Floppy (S or F)? f Floppy drive number (0 or 1)? 0 Floppy drive 0: (offline) Available floppy formats: DD 800 blocks Which format (# of blocks)? Now whether you want to actually do the format on a DEC RX50 drive is another question. According to Charles Lasner's voluminous posts on RX50 technical details, RX50 drives lack the required physical head-positioning accuracy to make a RX50 floppy that's guaranteed to be interchangable with other drives. Look at Charles's posts to alt.sys.pdp8 on the topic -- Tim Shoppa Email: shoppa(a)trailing-edge.com Trailing Edge Technology WWW: http://www.trailing-edge.com/ 7328 Bradley Blvd Voice: 301-767-5917 Bethesda, MD, USA 20817 Fax: 301-767-5927