Vintage Computers — 5
I have a tendency to tinker with multiple projects. In the end everything gets completed, but seldom in a linear manner unless there is urgency. When I started this journey wanting to archive and image floppy disks, I remembered other projects that had been simmering in the depths of my mind.
One such project was wanting to reconfigure the 486 hard disk.
Years ago I installed Slackware 11.0 on the 486 system in a multi-boot configuration using GRUB 1. That was a challenging project.
The adventure turned out to be proof-of-concept only. I was asking too much of The Little Engine That Could, with limitations of 16 MB of RAM, a 100 MHz Cyrix Hybrid CPU, and a 10 Mbps network controller. Using Linux on the system was painful. Everything was slow.
While the project was fun, the system mostly was unusable on the 486 system. I can understand how Linux did not gain notable momentum partly until Pentium systems became available. More RAM is needed to have any hope of running equitably on a 486. Further, the Linux kernel was always 32-bit and 486 systems were designed when 16-bit operating systems were popular.
I wanted to remove the Slackware 11.0 installation and revert the system to only the original MS-DOS and Windows for Workgroups (WFWG) configuration. When I embarked on the multi-boot project I replaced the original Conner 540 MB hard disk with a Maxtor 20 GB disk. I could continue using the same 20 GB hard disk, but I wanted to revert to a smaller disk.
The original Conner 540 MB hard disk that came with the 486 was in the hard drive junk collection. The disk was still functional. I selected that disk to restore the 486 to the original operating system.
Having been away from the DOS world for many years I wanted first to create a test disk in a VirtualBox virtual system. I had images of the MS-DOS 6.22 floppy disk set.
MS-DOS used the FAT-16 file system and could support a maximum partition size of 2 GB. There are infamous BIOS designs limiting which hard disks can be used. The Conner disk satisfied the limitations.
After creating a blank virtual hard disk, in the virtual system the MS-DOS floppy disk installer refused to proceed.
I had created a Windows 3.1 virtual system. That should have succeeded but I wondered if should have chosen a DOS system. A nominal quirk with VirtualBox is no DOS option in the default pick list. The user needs to select the
Other option to find the DOS option.
I created a DOS virtual system. Again the floppy disk installer refused to cooperate.
I exited the setup dialog using
F3 and at the
A: prompt manually typed
setup. This seemed to proceed better, but the only available option was installing to another floppy disk. For some reason the installer did not see the virtual hard disk.
The dialog failure message was about the floppy disk being an “upgrade.” I decided to try installing with MS-DOS 6.0 floppy disks. Yet this is one of the floppy disk sets that I had copied only the files rather than create images. I needed to create bootable images of those floppies.
I could have created images using another computer, but as I often do, I decided to venture into the land of the unknown and untested. I tend to justify this energy expense as “improving my skills and knowledge.”
I created a blank 1.44 MB floppy disk image:
dd if=/dev/zero of=empty-floppy.img bs=512 count=2880
I created and mounted a loop device to the image file:
losetup -f losetup /dev/loop0 empty-floppy.img mkfs.msdos /dev/loop0 mount /dev/loop0 /mnt/msdos
From my archived copied files I copied the floppy disk files to the mounted floppy disk image.
In my virtual machine the new floppy image refused to boot.
Perplexed and tired, I shelved the project for a day.
More to come.