First post, by serialShinobi
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- Newbie
Hello. I have, after several months, installed DOS 6.22 on a motherboard with a 486 chipset and Plug'n Play BIOS.
Thanks for advice I have been given by this forum.
Now I need help getting my facts in order. I have done some reading but I wonder about the opinions of those here with more experience than I have with the industry of IBM clone PCs.
My Configuration:
It's an ESA TF486 motherboard that has an (Acer) Finali M1487/89 PCI chipset and Award BIOS and Pheonix PnP BIOS. The hard disk is a 1998 Samsung 3.4 GB VG33402a. The IDE interface is a 1997 Promise Ultra33.
MS-DOS 6.22 Install steps:
Using a CF, I had load an image file of a bootable DOS floppy using grub4DOS. Then I partitioned the hard drive drive with command "2/PRI:2048" (courtesy of Computer Hope website). Then "Format C: /S". I used floppy images in virtualbox to install DOS 6.22 and xcopy /S to copy installed OS files to a CF card. I used attrib to be able to copy IO.SYS and MSDOS.SYS from C:\. I booted my DOS 486 from it's hard disk and applied CF card directories I copied from the DOS VM.
I had to use a vboxmanage command from oracle virtualbox to create a vmdk image file assigned to the CF card.This is the only way to transfer files from both the VM *and* the computers of the 1990s. https://youtu.be/1CtwnnqdNRY
and xclusive which prevents windows from blocking access to the CF card https://www.kaufmann.no/roland/dskacl/
I believed that BIOS of DOS days can be very proprietary, with no standard, and a cause of my trouble installing DOS.
Now I think it may have been DOS 6.22 all along. Paraphrasing the 1996 BIOS Boot Specification by Pheonix, et al (attached at end of this post): There are several hardware improvements that handle INT13h routines outside of BIOS.
According to Wikipedia
https://en.m.wikipedia.org/wiki/INT_13H
DOS is a real mode operating system where INT13h is tightly bound to BIOS:
The BIOS typically sets up a real mode interrupt handler at this vector
[INT13h] that provides sector-based hard disk...read and write services using (CHS) addressing.
Also I believe my hardware could boot the new way, outside BIOS. The specification suggests my hard disk is capable of being enumerated within PnP BIOS as a list of (IPL) boot devices. The specification also suggests the option ROM on my promise disk interface is made for use with Plug n' Play and this is why the restrictive BIOS scheme was bypassed.
Could DOS real mode have prevented my configuration from bypassing BIOS? Is Windows 9x and protected mode a reason why my configuration made it so easy to install?
Can a BIOS manufacturer have their own way of booting a hard disk? So a BIOS vendor could handle INT13h in a way differing from other BIOS vendors?