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External 720K floppy drive IBM XT

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    #16
    Two possibilities: (1) speed error, (2) alignment issues. Speed is easiest to tackle. Use any RPM-reading program, such as IMD. Alignment is a bit thornier, but doable.

    Comment


      #17
      Originally posted by Chuck(G) View Post
      What Stone said. And--you are using DS2D 3.5" floppies and the DSHD, right?
      Disks are Mitsubishi IBM format MF2-DD
      Not all those who wander are lost. - J. R. R. Tolkien

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        #18
        Originally posted by robbo007 View Post
        Disk made on the external floppy does not read on another computer. I get sector errors.
        Because of this:
        Originally posted by rmay635703 View Post
        I don’t think that’s it, I had a stack of 5 drives all of them had the issue that they could only read disks made by another 4865 on the 5150, could never move data from another 720k system to the pc.
        You may be dealing with a bad batch of drives. Unless you're really good I don't think aligning a 3" floppy drive is something you'll have much success with as a novice. I wouldn't even attempt to align a 3" floppy drive and I'll bet you're probably better off just chalking it up to what it is and moving on.
        PM me if you're looking for 3" or 5" floppy disks. EMail For everything else, Take Another Step

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          #19
          Would be good to see what floppy drive controllers everyone is using here. To see if it's a compatibility issue. I'm just surprised that so many drives are showing the exact same problems.
          Not all those who wander are lost. - J. R. R. Tolkien

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            #20
            Originally posted by robbo007 View Post
            I'm just surprised that so many drives are showing the exact same problems.
            That's why it could be a manufacturing issue.
            PM me if you're looking for 3" or 5" floppy disks. EMail For everything else, Take Another Step

            Comment


              #21
              Originally posted by robbo007 View Post
              Would be good to see what floppy drive controllers everyone is using here. To see if it's a compatibility issue. I'm just surprised that so many drives are showing the exact same problems.
              All PC disk controllers are NEC 765 at their core. They may have extra registers and add-ons, but the basis and pretty much the programming is the same. The one good thing about PC designs. Of course, modern PCs don't have legacy floppy controllers...

              Seems to me that the OP hasn't replied to this thread lately, so he's either ignoring posts or he's already solved the issue.

              Comment


                #22
                Originally posted by Chuck(G) View Post
                Seems to me that the OP hasn't replied to this thread lately, so he's either ignoring posts or he's already solved the issue.
                The person you quoted from earlier today was the OP so I think it is still an active topic.

                Comment


                  #23
                  Okay, so where are the results from Anadisk and IMD? We've told you how to figure out what the problem is.

                  Comment


                    #24
                    Originally posted by Chuck(G) View Post
                    Okay, so where are the results from Anadisk and IMD? We've told you how to figure out what the problem is.
                    Hi Chuck, I've ran the floppy disk created on the external drive through AnaDisk

                    Give me a "Failed recalibrate" on the drive and disk. I don't see it even reading the disk. No lights go on the drive. Just fails straight away. hmmmm Could this be due to the use of external drive and the DRIVER.SYS ?

                    Reading the disk on Anadisk on another system I get:
                    Double Sided Double Density
                    Interleave:1:1
                    Side 0 sectors ID 1-9
                    Side 1 sectors ID 1 -9
                    Last edited by robbo007; February 4, 2019, 04:18 AM.
                    Not all those who wander are lost. - J. R. R. Tolkien

                    Comment


                      #25
                      I've ran the XT diagnostics disk and when testing the speed of the drive I get this error: 7303. The formatting part of the diagnostics test for the drive works fine but it then goes on to test the speed. Something that is does not seem to do with the internal floppy drives. Maybe IBM knew about these problems and tested for it?
                      Any ideas where too find the error code description?
                      Not all those who wander are lost. - J. R. R. Tolkien

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                        #26
                        Quote Originally Posted by Chuck(G) View Post
                        Okay, so where are the results from Anadisk and IMD? We've told you how to figure out what the problem is.

                        If I scan a disk formatted on the external IBM drive under AnaDisk I get errors like:

                        Read track ID 41, expected 40

                        on all to about track 48 then I start getting data error.
                        Not all those who wander are lost. - J. R. R. Tolkien

                        Comment


                          #27
                          So you get a message like "Read track 3, expected 2"?

                          I can guess two causes. The first is that your drive alignment is out. The second is that the drive positioner (usually a leadscrew affair) is full of crud, hardened grease, dirt, whatever so that things cannot move smoothly.

                          If this is a drive that hasn't been touched by anyone with a screwdriver, then the latter is probably the situation.

                          Comment


                            #28
                            Originally posted by Chuck(G) View Post
                            So you get a message like "Read track 3, expected 2"?

                            I can guess two causes. The first is that your drive alignment is out. The second is that the drive positioner (usually a leadscrew affair) is full of crud, hardened grease, dirt, whatever so that things cannot move smoothly.

                            If this is a drive that hasn't been touched by anyone with a screwdriver, then the latter is probably the situation.
                            I finally managed to find a post about this over on Vogons. Using good old "Dave Dunfield's ImageDisk" I aligned the drive and now it works perfectly. A note. When using ImageDisk with the external drives you must use the /4 parameter to load it. This way ImageDisk can access your external drive.

                            Here's the post if anyone has the same problem: https://www.vogons.org/viewtopic.php?f=46&t=77145
                            Not all those who wander are lost. - J. R. R. Tolkien

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