Loading ...
Sorry, an error occurred while loading the content.

Mitsubishi 2896 8" Drive to PC

Expand Messages
  • Kyle Owen
    Hi all, I mentioned recently that I received a couple of NEC APCs and got one to actually boot. However, I am missing lots of DOS utilities, including
    Message 1 of 6 , Sep 30, 2012
    View Source
    • 0 Attachment
      Hi all,

      I mentioned recently that I received a couple of NEC APCs and got one to actually boot. However, I am missing lots of DOS utilities, including everyone's favorite, EDLIN. Thus, I'd like to make some fresh boot disks using Dave's IMD utility. 

      I have been asking around the university, and managed to find a couple of DSDD 8" floppies, and *three* Mitsubishi 2896 drives. I have some cables, and I tried making a floppy cable adapter as per Dave's instructions here: http://www.classiccmp.org/dunfield/img54306/cnct.htm


      My ohmmeter shows good continuity between both sides of the adapter. I'm just not sure what's going on.

      I have tried using the jumper settings as they came to me, as well as the default values in the manual, Fig. 6-1, on page 34 of the .pdf (found here: http://maben.homeip.net/static/S100/mitsubishi/diskette/Mitsubishi%20M2896-63%20Half%20Height%208inch%20DSDD%20floppy%20drive%20198401.pdf). 

      Every time, though, I get a seek error on boot. My machine is a Pentium 4 Dell running MS-DOS 6.22. The error is the same whether the drive is connected or not. I have no logic analyzer, so my trusty old Tek 465 'scope will have to suffice. I have yet to get it out to watch the step line, though I suppose that would be a a logical next step. All drives spin when the 24V is applied, and when the 5V comes up (from the computer), the drive stops. 

      Any ideas? Have any other MARCHians been successful hooking this (or a similar) drive up to a modern PC?

      Thanks, and 73!

      Kyle, W4GNU
    • David Gesswein
      ... I have gotten an 8 drive to work with a PC. It took some fiddling but was long enough that I don t remember exactly what. I was playing with the BIOS
      Message 2 of 6 , Oct 1, 2012
      View Source
      • 0 Attachment
        On Sun, Sep 30, 2012 at 09:28:20PM -0500, Kyle Owen wrote:
        > Hi all,
        >
        > Any ideas? Have any other MARCHians been successful hooking this (or a
        > similar) drive up to a modern PC?
        >
        I have gotten an 8" drive to work with a PC. It took some fiddling but
        was long enough that I don't remember exactly what. I was playing
        with the BIOS settings and drive jumpers. If your PC moves the heads
        on startup the 8" drive should do the same. If not check the
        drive select/ready/track 0/step.
      • joshbensadon
        ... I have not done this before, sounds like something I would like to do. But if I still may throw in my 2 cents worth... Most FDC s will home the head(s) on
        Message 3 of 6 , Oct 1, 2012
        View Source
        • 0 Attachment
          --- In midatlanticretro@yahoogroups.com, David Gesswein <djg@...> wrote:
          >
          > On Sun, Sep 30, 2012 at 09:28:20PM -0500, Kyle Owen wrote:
          > > Hi all,
          > >
          > > Any ideas? Have any other MARCHians been successful hooking this (or a
          > > similar) drive up to a modern PC?
          > >
          > I have gotten an 8" drive to work with a PC. It took some fiddling but
          > was long enough that I don't remember exactly what. I was playing
          > with the BIOS settings and drive jumpers. If your PC moves the heads
          > on startup the 8" drive should do the same. If not check the
          > drive select/ready/track 0/step.


          I have not done this before, sounds like something I would like to do.
          But if I still may throw in my 2 cents worth...

          Most FDC's will home the head(s) on start up/init.
          So, with power off, spin the motor shaft to move the head out and turn on the power to watch it go "home" to track 0. Here's a good way to test stepping and the track 0 line.

          I've not done this before, but my question would be around the Head Load line? Do the 5-1/4" drives even have a "Head Load"?

          While we're on the subject... how do double sided disks work? I mean, are the write currents so low that the magnetism doesn't bleed through to the other side? or do they skew the side 1 and side 2 tracks? or both?

          Cheers,
          Josh
        • Kyle Owen
          Good news, everyone! I was able to get the 8 drive working just fine. I ended up making another passive adapter, this time using a 5.25 floppy edge
          Message 4 of 6 , Oct 3, 2012
          View Source
          • 0 Attachment
            Good news, everyone! I was able to get the 8" drive working just fine. I ended up making another passive adapter, this time using a 5.25" floppy edge connector. Now it can tie into a normal floppy ribbon cable. I had to play with some jumpers, but I finally found some that worked. If anyone wants a better write-up for connecting the Mitsubishi 2896 to a computer, just let me know. I'll get something written up. I also should mention that the 150 ohm terminator is way too small for this particular machine, so I moved up to 1k terminators. I think it was also working without the terminator altogether, but I'd have to try it again just to make sure.

            I have successfully copied both the MS-DOS boot and list disks to 8" floppy, and both work great. ImageDisk, although very low-level, is quite easy to use. I guessed on some parameters like interleave, but it works just fine. Sweet! CP/M is next, though I'll have to forfeit the list disk to do that. I only have a few 8" that people have dug out from their filing cabinets and bookshelves, and several are either SS,SD or SS,DD. Bummer!

            Kyle

            On Mon, Oct 1, 2012 at 7:57 PM, joshbensadon <no_reply@yahoogroups.com> wrote:
             

            --- In midatlanticretro@yahoogroups.com, David Gesswein <djg@...> wrote:
            >
            > On Sun, Sep 30, 2012 at 09:28:20PM -0500, Kyle Owen wrote:
            > > Hi all,
            > >
            > > Any ideas? Have any other MARCHians been successful hooking this (or a
            > > similar) drive up to a modern PC?
            > >
            > I have gotten an 8" drive to work with a PC. It took some fiddling but
            > was long enough that I don't remember exactly what. I was playing
            > with the BIOS settings and drive jumpers. If your PC moves the heads
            > on startup the 8" drive should do the same. If not check the
            > drive select/ready/track 0/step.

            I have not done this before, sounds like something I would like to do.
            But if I still may throw in my 2 cents worth...

            Most FDC's will home the head(s) on start up/init.
            So, with power off, spin the motor shaft to move the head out and turn on the power to watch it go "home" to track 0. Here's a good way to test stepping and the track 0 line.

            I've not done this before, but my question would be around the Head Load line? Do the 5-1/4" drives even have a "Head Load"?

            While we're on the subject... how do double sided disks work? I mean, are the write currents so low that the magnetism doesn't bleed through to the other side? or do they skew the side 1 and side 2 tracks? or both?

            Cheers,
            Josh


          • David Gesswein
            ... Good to see it working. You can use a hole punch to make the DS holes in the SS disk jacket and it will normally work ok. SD will also normally work ok DD.
            Message 5 of 6 , Oct 4, 2012
            View Source
            • 0 Attachment
              On Wed, Oct 03, 2012 at 09:56:38PM -0500, Kyle Owen wrote:
              > I only have a few 8" that people have dug out from their filing
              > cabinets and bookshelves, and several are either SS,SD or SS,DD. Bummer!
              >
              Good to see it working. You can use a hole punch to make the DS holes in
              the SS disk jacket and it will normally work ok. SD will also normally
              work ok DD. After you write the disk dump it again to see if it has errors.

              If you keep watching you probably can get some at an ok price on ebay.
              Some brands are having oxide shedding problems. Others may know which to
              avoid.
            • joshbensadon
              ... That s great news Kyle! It s always exciting to hear success stories. You know who would probably really like a write up of it? Herb Johnson. He collects
              Message 6 of 6 , Oct 4, 2012
              View Source
              • 0 Attachment
                --- In midatlanticretro@yahoogroups.com, Kyle Owen <kylevowen@...> wrote:
                >
                > Good news, everyone! I was able to get the 8" drive working just fine. I
                > ended up making another passive adapter, this time using a 5.25" floppy
                > edge connector. Now it can tie into a normal floppy ribbon cable. I had to
                > play with some jumpers, but I finally found some that worked. If anyone
                > wants a better write-up for connecting the Mitsubishi 2896 to a computer,
                > just let me know. I'll get something written up. I also should mention that


                That's great news Kyle! It's always exciting to hear success stories.

                You know who would probably really like a write up of it? Herb Johnson. He collects all these write ups and posts them on his web site for others to follow.

                Cheers,
                Josh
              Your message has been successfully submitted and would be delivered to recipients shortly.