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IBM PS/2 Model 30/286, OS/2, and XT-IDE

SwissArmyTin

SwissArmyTin

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Greenville, SC
My Model 30/286 has a dead HDD, so as a replacement I ordered a Blue Lava ISA XT-IDE + CF adapter. I was hoping to get a dual boot install of OS/2 1.0 and 1.2, however I know well enough that even later editions of OS/2 are extraordinarily picky about hard disks, BIOSs, and hardware configurations, so I was wondering if anyone had any experience installing OS/2 1.x on an XT-IDE drive and if there's any pitfalls I should keep an eye out for. Aside from the XT-IDE card, the machine is completely stock and I'm not planning on making any modifications, aside from replacing the Dallas rtc.

Thanks!
 
I wouldn't hold my breath. 16-bit OS/2 doesn't have a BIOS disk driver. You'll almost certainly need an XT-IDE specific 16-bit OS/2 driver.
 
i don't see why it won't work.
XT-IDE simlply replace the bios routine by it's own, and as far i know is totally compatible with everything.
as long OS/2 have an INT13 driver, and i really don't see why it won't for some obvious reason, it should work.
the limitations are going to be the partition size HPFS or FAT can handle.
 
whaka said:
i don't see why it won't work.
XT-IDE simlply replace the bios routine by it's own, and as far i know is totally compatible with everything.
as long OS/2 have an INT13 driver, and i really don't see why it won't for some obvious reason, it should work.
the limitations are going to be the partition size HPFS or FAT can handle.
Click to expand...
One can't use INT13h BIOS functions with OS/2 1.0; the cost of switching from protected mode into real mode is too high. OS/2 1.0, 1.1, and 1.2 used DISK01.SYS (or DISK02.SYS) to handle all disk accesses while in protected mode. DISK*.SYS included only a limited selection of supported controller types. AFAIK, there is no XT-IDE driver patch for OS/2 1.x.

OS/2 1.x will not run on a stock 30/286. Even 1.0 needs 1.5 MB of RAM and it is necessary to turn off the DOS compatibility box to run any OS/2 software beyond a simple command prompt. Presentation Manager pushes the needed RAM up to 4 MB but the 4 MB configuration is quite responsive under 1.3. Getting OS/2 to run on an AT class machine could prove expensive these days.
 
what i mean (very badly maybe) is OS/2 necessarly have it's own "INT13 compatible" driver that take over the bios.
otherwise, how OS/2 could be able to talk to the floppy drive for exemple ?
the XT-IDE, like any other kind of bootable controller can be used without any special driver with any OS, bios dependent or not, as long they don't use their own way to be accessed. i can be wrong, but i understood things like that.

to be clear the scheme look like this, machine start in real mode > OS/2 start to boot in real mode > OS/2 take over the bios with his driver and continue booting as long the controller is INT13 compatible.

the only pitfalls i can see are the drive/partition size the OS/2 driver and filesystem can handle.
for early version, i don't know.
 
The OS/2 drivers go directly to the hardware of the controller bypassing INT13h. This isn't Win95 after all. SCSI controllers came with driver disks that provided a replacement DISK01.SYS. I can't find if there were any revised DISK01.SYS drivers for IDE (16-bit) for OS/2 1.x. I think there were but memory ain't what it used to be.
 
ah yes... my bad, i just forgot it has to know IDE language.
i tried out of curiosity with OS/2 1.1 extended on my model 70 with a scsi controller he can't know because far too recent for him.
and of course, it failed to start fdisk, i guess because of that.
sorry, i was confused :D
 
Thanks for all the feedback, seems this'll be about just as complicated as I expected, haha.
I was planning on using a 64mb CF card with two 32mb partitions, as 32mb was the capacity of the original stock HDD in my PS/2. Hopefully that's enough breathing room for dualbooting and formatting shenanigans. I've been using Ontrack Disk Manager to partition drives in advance of OS/2 installation on other machines for newer versions of OS/2, which has gone off without a hitch as Ontrack has special formatting options for OS/2, however I'm not sure if it'll run on a 286 machine.
As for the memory, I'm not sure if I have any 1mb SIMMs, but I should be able to source enough to expand the system to 4mb if needed.
 
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