09/15/08: mounting .dsk images from OS9 by tfadden, | Category: OS-9 | 4 comments - (Comments are closed)

mounting .dsk images from OS9

Is there a utility/way to mount, or write to floppy .dsk images from within OS9.

IE, download .dsk images to my os9 systems hard drive, and then create a real disk from the image, or mount the image directly.

I can get them on the hard drive, but they are useless unless I can write a disk, or access the files.


Tim fadden

4 comments to mounting .dsk images from OS9

  • RobertGault

    Images of the type .dsk normally are byte per byte copies of the data sections of real floppy disks. The are intended for emulators running on PCs rather than real hardware Coco systems.

    The easiest way to create real floppies from .dsk or .os9 images is to do so on a PC. There are several programs for this purpose depending on your machine and OS.

    It should be possible to create a real floppy from a .dsk image using a real Coco but it will be involved and I don’t remember reading that anyone has actually done it. You already have the image on a real OS-9 hard drive so you have completed the first step. Now you need to write a program that reads the image a byte at a time or perhaps 256 bytes at a time and transfers them to a floppy.

    For this to work, you must know the format of the image. Is it single sided 35 track, double sided 40 track, or something else? How is the image configured if double sided? Most interleave tracks from front and back disk sides. Knowing the format, your program must write sectors from the image to the correct sectors on the floppy.

    Do you feel up to the job of writing a program to do the above or are you going to use the conventional method of creating the floppy on a PC with existing software?

  • tfadden

    Ya! Hoo!

    After more looking and searching and reading, I found just what I need! An OS9 utilitie to read os9.dsk images! get a dir and read the files off of it! I already had it on my coco system in an lzh archive. Now all I have to do is test it.

    I’ll keep you posted.

  • tfadden

    Ok, I have gotten a bit further. os9dsk works on single sided, double sided, 40 and 80 track disks. It has one problem. Large files will crash and lock up tho computer. IE os90defs and vtiodefs both in the defs directory are too large. I do have the C source, so at some time I will take a wack at trying to figure out the problem probably the variable used for file size is not correct.

    So I went to the Nitros9 site and got the basic09 program convdsk.b09.

    This one as is will only work with single sided images. I messed around in VCC, and split up a 40tDS image into two 40TSS images with the defs Dir and some of the CMDs in on it to make space for a single sided boot disk image. on the other image I have OS9Boot, Cmds, Sys, sysgo and startup. This boots fine in the emulator. Sooo I got those over to the coco, used convdsk.b09 to create 2 single sided disks. Everything completed with no errors, and all the files ident good etc.

    When booting the Nitros9_6809 SS disk I almost get all the way.

    this is the output:
    KREL Boot Krn tb0 ………………………………………………………………
    ……………………………………………………………..bKrnP2 IOMan Init RBF
    rb1773 D0 D1 D2 DD SCF VTIO KeyDrv JoyDrv SndDrv CoVDG Term W W1 W2
    W3 W4 W5 W6 W7 PipeMan Piper Pipe Clock Clock2 i2xtot*j

    and then boot FAILED

    The end of the boot process seems to be fine untill the garbage at the verry end Clock2 is the last module in OS9Boot.

    Does the 6809 version have to be on a 6809, or will it work with a 6309?

    Would any one have any hints at what could be causing the boot to fail?

    I have used ident, dmode etc to check settings on nitros modules with the existing os9 modules that are working for me.

    The hardware I have is: 512k coco3 6309, Disto 4in1 no multipak, Puppo keyboard adapter, and Roy’s excellent VGA adapter on a 17in LCD.

    Any pointers or places to look would be appreciated.

    Tim Fadden

  • RobertGault

    I think your boot failed with error $EA non-existant module. You should check that sysgo is in your root directory if not within the os9boot file.