PC-DOS 2.x

edited August 2019 in Product Comments

PC-DOS 2.x

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  • The Jan'83 Manual is for DOS 2.0, not DOS 2.1 as labelled here

  • The manuals should be fixed now.

  • When i format C: it shows me this error "Formatting...Track 0 bad - disk unusable
    Format Failure" Any solution?
  • @PrussiaBoi

    What emulator/hardware are you using?
  • edited November 2020
    I use VirtualBox
  • I believe the problem is that the DOS 2.x formatter has issues with hard drives that use 63 sectors per track. Hard drives on the original IBM PC only used 17. Enough tools were hard coded for that, that RLL controllers with 26 sectors per track often had to offer sector translation.

    Also, remember that DOS 2 only supports drives less than 16MB. 10MB was typical.

    Anyway, there are two options -
    1: Format the drive using DOS 3.3 or later. Then SYS with DOS 2.x.
    2: Use an emulator such as PCE, PCEm, or MESS. These have more accurate emulation.

    BTW, at least older versions of Virtualbox do not support 360k floppy disk images, and IBM PC-DOS 2.x does not support 720k or 1.44mb. It will, however boot MS-DOS 2.x OEM disks, such as Kaypro 2000, that support 720k.
  • I tried to write the DOS 2.1 disk01.img file to a 360k 5.25 floppy (1s/dd) using my IBM5060 + cf-xt "hard drive" to ferry over the files.. I first formated "format a:" and then ran "dskini a: disk01.img" and it does run and write to the disk an dcompletes sucsessfully. However, it wont boot in the IBM 5050. The floppy and the drive are good (I wrote DOS 1.1 with teldisk to the same floppy and it boots fine. Is the use of dskini even possible or die I do something wrong?
  • Not familiar with "dskini", but many DOS disk writers don't properly support 180k, 160k, or 320k formats. In retrospect, we should have included ImageDisk files in the archive.

    For the moment, try this: use "bin2imd" included with ImageDisk to convert the IMG files to IMD format, and then write those. Use the command:

    BIN2IMD DM=5 N=40 SS=512 SM=1-9 /1

    Or alternatively, it should be possible to resize the 180k images to 360k with WinImage.
  • edited June 2021
    @SomeGuy: That problem (that you encountered in November 2020)'s limited to older versions of VirtualBox. VirtualBox 5.1 and 6.0, at least, fully support 360k 5.25 floppy images (and also 320k, 180k, and 160k ones).
  • version 2.1 runs fine in PC-Emu 1.7, had to use DTC 5150x HDD controller in order to install it on fixed disk drive
  • Does anybody know why commands like @echo off produce a "command not found" or similar error in 2.1? This does not happen for me on ver. 3.3 and higher. Is there anything special in they batch files syntax for this version of DOS? Curious to know if somebody could shed some light on this for me as I fail to find anything online.
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