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Feel free to post tests on really old hardware configurations that also can run your OS. The older the better.

I just managed to get an 80386DX from 1988 to start with my VGA card and keyboard, and I'm able to change BIOS settings and all. Now all I need is to find a functional HD/FDD controller for the AT-bus and a harddisk (or floppy disk) that also works. Then I need an OS image that I can boot.

Hi,

How about making this some sort of "post here if you want someone to test your OS on real ancient hardware" thread? Or does something like that already exist?

Regards,
Shikhin

Shikhin wrote:Hi,

How about making this some sort of "post here if you want someone to test your OS on real ancient hardware" thread? Or does something like that already exist?

Regards,
Shikhin

I don't know about that. Testing OSes on real ancient hardware is not so easy. These PCs often don't have 1.44MB floppies, and they don't have GRUB or other bootloaders installed either. That means it is real complex to do these tests. I plan to prepare a harddisk with a real boot-loader on a more modern PC, and then place it in the ancient one.

Shikhin wrote:How about making this some sort of "post here if you want someone to test your OS on real ancient hardware" thread? Or does something like that already exist?

I encourage before starting a thread like this for example, that you should search the forum(S) for a similar one. Opening ancient questions are not liked. However, i believe it to be fine if its a thread like this.

on topic

rdos wrote:I don't know about that. Testing OSes on real ancient hardware is not so easy. These PCs often don't have 1.44MB floppies, and they don't have GRUB or other bootloaders installed either. That means it is real complex to do these tests. I plan to prepare a harddisk with a real boot-loader on a more modern PC, and then place it in the ancient one.

I think its always interesting to see. Watching old hardware come to life with code many years after its existence, knowing it can still run it. Another reason why i'm into operating systems for 8086 computers made now doing so much on so little.

rdos wrote:Then I need an OS image that I can boot.

Good luck, post images.

Hi

My IBM 8530-021 with an 8086 doesn't have a Protected Mode, so testing is impossible. But for this I've an 386 DX pc

Bad news. The CMOS chip seems to be damaged (there probably is a battery-backup in it), and when I change the settings, the computer reboots and comes up with "incorrect cmos", and the parameters I entered are lost. The default-parameters are no good with a 360kB 5.25 inch floppy, and a hard-drive configuration that I cannot match. My only hope is that keeping the board running for a while might recharge the CMOS battery.

The Cyrix 486 board I also have (and which I used for many years), doesn't boot, so that one seems to be beyond any hope.

I wonder if old computers like these can still be bought in second-hand shops?

Our company also have a 386 PC/104 board, which might work as a last resort, but it is not really that old.

I have a Compaq 386sx laptop here. All it needed to revive it was a new CMOS battery. It also has what would appear to be one of the earliest ever graphical BIOSes

Owen wrote:I have a Compaq 386sx laptop here. All it needed to revive it was a new CMOS battery. It also has what would appear to be one of the earliest ever graphical BIOSes

Mine doesn't have the usual battery, rather has a chip from Dallas semiconductors called DS1287.

Owen wrote:I have a Compaq 386sx laptop here. All it needed to revive it was a new CMOS battery. It also has what would appear to be one of the earliest ever graphical BIOSes

hehe that reminds me of an old ibm machine i once had, where the "bios" was more like a graphical file manager, with built in fat12 & mouse support. i'm not sure exactly how it all fitted together, but you could run games directly from that interface, or click some menu to get to the IBM DOS prompt. fun times. weird systems all around

Apparently, Elfa has a replacement IC that costs $10. I might order one as I order some other components for my solar controller project.

In the mean time, I might try to configure some of the old IDE-drives with RDOS, so I'm ready to test.

bubach wrote:

Owen wrote:I have a Compaq 386sx laptop here. All it needed to revive it was a new CMOS battery. It also has what would appear to be one of the earliest ever graphical BIOSes

hehe that reminds me of an old ibm machine i once had, where the "bios" was more like a graphical file manager, with built in fat12 & mouse support. i'm not sure exactly how it all fitted together, but you could run games directly from that interface, or click some menu to get to the IBM DOS prompt. fun times. weird systems all around

The thing I love about this Compaq, is that the BIOS setup program comes on a 720kb floppy!

As I browsed one of the candidate discs, a 125 MB drive, I not only discovered that it worked perfectly well, but it also contains a lot of source and ancient RDOS versions (2.3 - 4.4) that I had lost since. It has MSDOS 6.0 installed, NDOS command shell, and some diskeditor tools for DOS. Needless to say, I've copied all the content to my present harddrive before repartioning it.

Owen wrote:[The thing I love about this Compaq, is that the BIOS setup program comes on a 720kb floppy!

That doesn't sound very good. Chances are that the floppy no longer works. Few of my old floppies work, so that was a real bad choice for backup.

rdos wrote:Bad news. The CMOS chip seems to be damaged (there probably is a battery-backup in it), and when I change the settings, the computer reboots and comes up with "incorrect cmos", and the parameters I entered are lost.

That's perfectly normal behaviour if you forget to adjust the checksum. Use these steps:
1. save old value to temp
2. write out new value
3. sub temp from checksum
4. add new value to checksum
And you'll be fine. Checksum is stored at CMOS register 2Eh (high byte), 2Fh (low byte).

Somewhere deep in my chests there is a 386DX 40MHz with 8MB EDO DRAM, 256kB Realtek VGA and multi-IO card. That worked fine when I upgraded to the newer PC. Hope I can revive it one day for experiments.