I'm working w/ a 486 machine - it has a BIOS from 11/1992; all the HDD options stop at 504MB unless you enter cylinder/heads/sectors.
I used a DDO software called OnTrack and that was able to quickly and easily see all 2GB on the CFCard, and partition it into 4 500MB partitions; but only one bootable.
Many friends tell me MS-DOS 6.22 should be able to see the full 2GB w/o
DDO software - am I missing something?
Its a BIOS limit, not a DOS limit that you're seeing. In order to
bypass the DOS extender you'd need a more recent BIOS which would be hit and miss depending on whats on board on your 486.
When DOS boots it gets the boot information from BIOS, so if BIOS can't see more than 500Mb which was a hard limit for some time, DOS will only ever see that initially unless you load the extender to tell DOS about
the rest of the space BIOS can't tell it about.
Perhaps you can try some different numbers from known 2GB disks of the era?
A better solution that I would propose is getting a 16-bit ISA network card for your 486 that has a socket for a boot PROM. Then you can use
the XTIDE Universal BIOS and your 486 will be able to see and use larger drives without having to bring any software into the picture. (There are also some multi-IO and IDE cards that have boot rom sockets, but in my experience these are rarer and harder to find than a NIC card.) I've
done this for both my 386 and my 486 and it works very well and is hassle-free.
They're hard to get, you say? I thought that was an easy solution in
2o23... Jesus!
XTIDE themselves aren't hard to get, but you probably don't really want
an XTIDE card for your 486 because they're 8-bit cards. What you want is
a network card or an IDE Multi I/O card with an empty boot ROM socket.
The later, the IDE Multi I/O card with an actual socket are the things that are hard to get. Network cards with a rom socket are relatively
easy to come by these days and work great. Then you can just get a
EEPROM with the 386+ version of the XTIDE universal BIOS, stick it in
the network card, and it'll take over drive translations for you.
Also, if you're manually copying .IMG files to floppy disks, I *highly* recommend you look into getting a Gotek with the FlashFloppy firmware on it. It'll make your life *way* easier.
Oh - I know, and appreicate the Gotek suggestion; I looked at it but
chose CFCard for a few reasons... this particular 486 has a network
card w/ ethernet that I can transfer files over, and I have a couple
other solutions - I was really just catching video for a youtube thing later, and having fun doing so. :P
I thought I had it all figured out - use some 30 year old software to get around the 504MB limit... but now I'm stuck to writing .IMGs to 3.5" diskettes - jesus... :P
Oh, I wasn't suggesting it as an alternative to the CF card. The CF card replaced the mechanical hard drive. The Gotek replaced the floppy drive. This system that the BBS is running on (a 386) and the system I've been working on (a 486) both use CF as their 'hard drives' and have Goteks
for getting software onto and off of them (in addition to network controllers).
The handy thing about it is that you can just pull a bunch of software images from somewhere like WinworldPC, copy them to your USB key, and be installing them on your system a few minutes later.
I noticed in a later message you mention putting larger values in the custom bios settings. You can put whatever values you want in there,
but the 500Mb BIOS limit still remains. I remember having to use OnTrack as well.. didn't think to much about it at the time. Times change though.
Thanks - understood. I'm thinking of ordering a GoTek board, as I want
to add the potentiometer and flash to the newest firmware... I know I
can order one, but it seems like a fun project to solder myself.
Yeah, I highly recommend the rotary encoder modification, and also
picking up one of the little OLED screens for it.
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