On Monday 18 September 2006 18:53, Gary E Kaufman wrote: --snip-- The RX02 cannot format "raw" diskettes. It can "re-format" RX01 diskettes to RX02 format diskettes and vice-versa. Software is available for both the PDP-11 and PDP-8 to do so. RX01 diskettes are essentially IBM System/34 compatible diskettes; i.e., IBM 3470 format. One can "create" IBM 3470/RX01 diskettes using "PUTR" on a PC which has a FDC connected to an 8" Shugart floppy diskette drive. See: http://www.dbit.com/fdadap.html for an excellent 8" floppy adapter for a PC. Cheers, Lyle -- Lyle Bickley Bickley Consulting West Inc. Mountain View, CA http://bickleywest.com "Black holes are where God is dividing by zero"

Jerome Fine replies: If you have any other questions about RT-11, please ask. Are you using V05.0x of RT-11 or V04.00 of RT-11? Both will work well, but the utilities in V05.0x are a bit improved. I strongly suggest that you make a backup copy of DY0: COPY/DEVICE DY0: DY1: then DIFF/BIN/DEV DY0: DY1: It is possible that DY1: is slightly out of alignment of dirt on the heads. I suggest that you use the backup copy of the RT-11 boot floppy and BOOT DY1: then FORMAT DY0: using a blank floppy and ... test the floppy on DY0: using INIT/BAD DY0: instead of DY1: and see if there is a better result. There are no "real" RX02 media - as has been explained by others. The RX02 media are ONLY an RX01 with the header being set to double density and the data area then being used at the higher density. As explained by others, a DEC RX02 floppy drive is NOT able to perform a RAW LLF (Low Level Format) of an 8" floppy. That was a decision by DEC to attempt to force DEC RX02 users to purchase 8" floppy media from DEC at prices which were many times higher. All 3rd party RX02 compatible drives which I ever used (such as DSD or Data System Design) had the ability to do an LLF of 8" floppy media. Or a Tony Duell suggested, first do the LLF as an RX01 on a non-DEC system, then change the media to double-density with the RT-11 command: FORMAT DY1: on the DEC RX02 floppy drive. As for other hardware problems, I am only a software person. My idea of fixing a hardware problem is the swap hardware. Tony would not approve, but I don't have the hardware background not the inclination to learn - I am too busy running a Prime number sieve program looking for Prime numbers. Sincerely yours, Jerome Fine -- If you attempted to send a reply and the original e-mail address has been discontinued due a high volume of junk e-mail, then the semi-permanent e-mail address can be obtained by replacing the four characters preceding the 'at' with the four digits of the current year.