Code archaeologist digs up oldest known ancestor of MS-DOS An intrepid code archaeologist has found and uploaded an early ancestor of what became MS-DOS, which ultimately sparked the IBM PC-compatible computer industry. The newly recovered boot disk contains 86-DOS version 0.1-C, which is the oldest known surviving copy of Seattle Computer Product's operating system. Yes, Seattle …
Just over a decade ago I had to convert a set of 3.5" floppy disks that my father had created using a Sharp "electric typewriter" and had problems in getting a working FDD, as well as the issue of converting the Sharp format in to something that could be read by a text editor. Eventually managed to image the floppies using 'dd' and then mounting them and running chkdsk from DOS in a VM (as newer disk utilities screwed the layout for some reason), and finally copying files off for conversion by a small C program I developed.
Thankfully never had to deal with FDD since!
A couple of years ago I dusted off (quite literally) my old original Apple ][. I had a box of 5 1/4" floppies, including the original Apple DOS boot disk. It was dated 1979, and the computer booted just fine from it after a little drive cleaning. I had a couple of disks with software I wrote back in the day. I was hugely surprised at how well everything worked.
I sold the Apple ][ on eBay for silly money. I put it up as an auction item, and was surprised how high the bidding went. The person that bought it was very happy to get it, and I was happy to get good money for it. It had been sitting in my garage for over 20 years, so I clearly didn't have a need for it anymore. I had bought it at a country auction for peanuts back in the early 90's, just to see if any of my old Apple disks would still be readable.
I do still have my first computer. It was an Ohio Scientific Challenger 1P (about 1977). A 6502 with a whopping 4K of RAM. That will need to be pried out of my cold, dead hand. It has too much sentimental value. I did a lot of lawn mowing, yard clean up, and chores as a kid to earn the money to buy the C1P.
[Author here]
Step 1. Test them.
Step 2. List the full specs.
Step 3. Take lots of pics showing outside, inside, identifying labels, etc.
Step 4. Post on ClassicCmp.org lists with links to the photos, in proper RFC 1855 style. Facebook Vintage Computer Mart. Give all the above info, your location, and your shipping abilities if any.
Back in the day, I used HyperCross on a TRS-80 to read and copy disks/files from many, many different systems and formats. It was amazingly powerful for the time. I think there was a less powerful version for the PC too. It was especially useful (and lucrative!) when local small businesses were transitioning from CP/M based systems to "IBM compatibles". About the only disks it couldn't read were hard sectored and weird stuff that did variable disk speed or sector sizes, which needed the proper drive type to even physically read the disk,
One place I worked, our despatch computer wasn't networked, so each day after the despatches were complete I had to pop a 3.5" floppy into the PC, dump the despatch file, then load said file on my PC.
Around 50% of the time, the 3.5" floppy wasn't readable after the 50 metre walk from the despatch bay to my office...
If you have a computer running MSDOS or Windows 7 etc then these days you need to recycle it. But if you have an S100 system that runs CP/M (I have a couple of IMSAI's and Altair 8800 systems plus a SOL) then you can just post them on ebay for a ton of money ... I'm not going to get filthy rich, they are too nice (and easy) to keep running!
at the risk of doxxing myself, I used to use a HP Microcomputer, running p-system, to manage remote equipment connected by a 300 baud then a 1200 baud modem. The machine hosted software that you could use to draw schematics of the remote equipment and see what remote things were happening in real(ish - only a couple of seconds delay) time.
I quite liked p-system - once I got used to it (was a CP/M and MS/DOS person previously)
I did have an S100 CP/M system - given to me for free (or very very little) from someone who worked at the Fleet Street paper that used them for something or other. The BIOS was for hard sectored drives, but it could read soft sectored ones if you let it spend a few minutes working out the timings on any particular 8" floppy disk.
Alas, it was far too big to keep during a move a few years later.
I can see why they're rare: almost anything will emulate them better than they ever were.
Them engineers in the 70's didn't even have an 8-bit byte (bytes were of a slightly more flexible form dependent on architecture, the 8-bit byte being referred to as an 'octet', but distinguished primarily for networking applications). There were 12 bit and 36 bit architectures, and all manner of headaches in between. Anarchy, I tell you. At least the 8086 used hex, rather than octal.
And here I thought IBM invented the word “byte” specifically for the System/360 architecture, which was the first byte-addressable range of machines. So they used it to mean “8 bits”, and nobody else used it to mean something different—at least, not before that time. If they did afterwards, they were just being perverse.
I have a memory of being told in the early 80s that IBM had used the size of a 'byte' to buy time at some point when minicomputers were biting into its market share: by announcing they were considering having a nine bit byte (can't remember if it would be eight data bits plus a parity bit or 'will support character sets with 512 characters') they ensured that enough customers would hold off buying someone else's eight bit byte kit and waste other companies' time redesigning for nine bit bytes.
When they had their new kit ready (the 360 range??) they went 'Oh, we've decided an eight bit byte is perfectly OK'.
Compared to the 8-bit CP/M systems available at the time, segmented addressing and 12-bit FAT's were a distinct improvement. Segmented addressing was less painful than bank switching and the FAT file system provided file size in bytes, thus eliminating the need for a ^Z to denote the end of a text file. Compared to a 32 bit address space and a more advanced disk format (e.g. various flavors of UNIX file systems), segmented addressing and 12 bit FAT's are a pain.
FAT was fine until you swapped a floppy disk without ensuring everything necessary had been written to it.
CP/M's file system would at least detect that - the infamous 'BDOS ERROR ON B' - whereas QDOS/86-DOS and early PC-DOS/MS-DOS would happily write the info for the old disk onto the new one.
Result: two corrupted floppy disks instead of one.
Still, it would be worth it for the Unix-like pipes and multitasking we were promised for MS-DOS 2.0 ...
This post has been deleted by its author
[Author here]
> Seattle Computer Services were a CP/M-86 licensee.
I have at least 2 important points to make about this, maybe more.
1. Seattle Computer PRODUCTS wrote QDOS. I do not know what Seattle Computer SERVICES is or was.
2. QDOS was released in 1979. CP/M-86 was released in 1982, the year *after* IBM's PC.
If you have just got your names and the initials wrong, then SCP may well have been a CP/M-86 licensee but this was several years after the fact.
3. QDOS and 86-DOS did not run on the PC and cannot be run in PC emulators. This is not a PC OS and it predates the existence of the PC.
4. So what if SCP was a CP/M licensee? QDOS targets a different processor architecture. It was not even written in the same language as CP/M: CP/M was written in PL/M; QDOS was written in 8086 assembly language. QDOS *couldn't* be written in the same language as DR's OS because DR didn't support the 8086 yet.
The _reason_ that software companies publish API references is so that 3rd parties can write their own software that targets the vendor's software. However, when you publish information, you cannot control what people do with it.
If you design a socket, with holes that prongs can connect into, and you publish the spec so that others can design connectors with compatible prongs, that means that others can also design sockets compatible with yours. That is how compatibility works.
If company A publishes its socket design, it is not "copying" or IP theft or reverse engineering or anything in any way nefarious if company B uses those specs to make a socket that's compatible with plugs designed for Company A plugs.
In this case DR published the API for its eight-bit 8080 OS and SCP implemented a compatible design for the very different, 16-bit, 8086.
Nothing stolen. Nothing criminal. Nothing wrong.
DR should have worked faster and published CP/M for other chips earlier.
The 8086 shipped in 1978. It took DR 5 years to support it.
I like DR. I like DR products. I respect Dr Gary Kildall's immense contributions to the PC industry. He deserved much better.
But DR was slow to respond and it paid the price.
DR's OS design for CP/M was not massively original work; it was clearly inspired by DEC OS-8.
https://en.wikipedia.org/wiki/OS/8
The OS/2 Museum has gone into the relationships in depth:
https://www.os2museum.com/wp/why-does-windows-really-use-backslash-as-path-separator/
io_uring is getting more capable, and PREEMPT_RT is going mainstream The Register 
Biting the hand that feeds IT
Copyright. All rights reserved © 1998–2024
