Ok, so I grabbed some DS/DD 3M 8" disks - I assume I can "MARK" them (reformat). But so far no luck. I never had disks on the 5110, so still learning about them on the 5120 - I assume they still need to be "MARK" just like the tapes are?
Here is a short video I made of the 5120 disk drives I have during startup of the system. I'll double check the fuses of the system tomorrow - the fuse behind the CRT was blown, so I'm thinking it's possible this system had some other electrical problems. IBM 5120 Disk Drive Example (benchtop experiment) - YouTube <https://www.youtube.com/watch?v=UxyDDx8LOGw> https://www.youtube.com/watch?v=UxyDDx8LOGw Much to investigate, but so many other projects - I may need to just put away these 8" drives for a while. OH, and I finally got to talk about the 5100 series. I'm not the best speaker and a couple mistakes I noticed - but mostly I hope I didn't horribly misrepresent your prior work. https://www.youtube.com/watch?v=JIJNrBaTenM -Steve On Mon, Jun 19, 2023 at 3:38 AM Christian Corti via cctalk < cctalk@classiccmp.org> wrote: > On Sat, 17 Jun 2023, Steve Lewis wrote: > > My only question is: how "universal" are 8" disk? This 5120 only came > with > > a single IBM 8" Diagnostics disk. It looks to be in fine condition, but > > I've no idea about the data. > > I can answer your question very quickly: > A 5120 is exactly the same as a 5110 plus 5114. This said, the diagnostics > and any software apply to both systems. > > You can take any 5110 floppy image and recreate a real floppy from it. The > format BTW is "the" standard IBM format. The 5114/5120 can handle > everything from single-sided single-density up to double-sided > double-density. The firmware OTOH has a predefined set called "formats", > ranging from 1 to 9, with an optional suffix indicating the number of > additional directory tracks (only available with DD). The list is > somewhere in the manual, e.g. format 1 is SS/SD 128 bytes/sect. 26 > sects/track, and format 8b (b=blank) is DS/DD 512 bytes/sect. 15 > sects/track. > IIRC format 1-3 are SS/SD, 4-6 SS/DD and 7-9 DS/DD > > Christian >
