Transferring DSK Images to Floppies

NitrOS-9 releases contain two 40 track double-sided images or one 80 track double-sided image. In order to transfer these disk images to a floppy disk suitable for use on a CoCo disk drive system, a 5.25" 360K floppy drive and/or 3.5" 1.44MB/720K floppy drive is recommended. The 1.2MB 5.25" floppy drive variants may seem to work, but will cause problems when being written on a CoCo system, so they are not recommended. New and refurbished 5.25" 360K floppy drives can be obtained from Cloud-9. Click here for more information.

Windows/DOS

For the example below, we will assume that the 3.5" 720K floppy drive is A:, and the 5.25" 360K floppy drive is B:

The tool required to transfer DSK images to floppies under DOS/Windows is DSKINI.EXE. Click here to download dskini.zip

Once DSKINI.EXE has been downloaded and extracted, call up a Command Prompt window under Windows (if you're not using MS-DOS), and insert a blank 5.25" 360K diskette into drive B. Presuming the image being transfered is nos96309l2v030200_ds40_1.dsk, type:

DSKINI /T40 /D B: NOS963~1.DSK

Note the use of the mangled filename form here. If you are running Windows, you can type the full length filename.

Once the transfer completes, you should have an exact image of the disk on the floppy, and can now use that floppy on a real CoCo.

Linux

For Linux users, download the fdutils 5 package at fdutils.linux.lu. Once installed, insert a blank floppy into your 5.25" 360K or 3.5" 1.44MB/720K drive. It will be either /dev/fd0 or /dev/fd1 depending on its position in the drive chain. For this example, we will assume /dev/fd1.

First, you must edit the file /usr/local/etc/mediaprm and add the following lines at the bottom of the file (you will have to edit this file as root):

"COCO40DS":
DS DD sect=18 cyl=40 ssize=256 tpi=48

"COCO80DS":
DS DD sect=18 cyl=80 ssize=256 tpi=96

Once this is done, you must tell Linux the type of disk in the drive. You must do this EVERY TIME you insert a disk into the floppy drive, as Linux "forgets" the disk type when you take the disk out:

setfdprm /dev/fd1 coco40ds

Now you can format the disk:

fdformat /dev/fd1

Once the format is complete, transfer the image as follows:

dd if=nos96309l2v030200_ds40_1.dsk of=/dev/fd1

Once the command is complete, the disk will contain the image and can be used in a CoCo disk drive system.