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How to format a hard drive from DOS 1.25?

Wat?

What exactly are you doing?

MS-DOS 1.25 does not support hard disks unless you have one of the rare special ports-and associated hardware that does. Off the top of my head the only versions that support that are MS-DOS 1.25 for the Eagle 1600 (If anyone has the system files and low level formatter, please let me know!) and an IBM PC-DOS 1.x "patch" for use with a Davong hard disk controller. I suspect there may have been one or two others.

DOS 1.x does not support subdirectories, so there would be no "deltree".
 
DOS 1.x was roughly akin to CP/M 80. If you had the OEM kit (your 1.25 may well be one of those customized by vendors), you could implement hard disk support, but it was rather limited (12 bit FAT and 16-bit sector numbers).

And, like CP/M, a single "flat" directory structure.
 
Well the story is that somebody donated a working Corona Data Systems PPC-400-22 "luggable" that has a hard drive installed, and company policy states that I can't sell anything that contains data from the previous owner.

The system memory is very low, (112kb available to DOS is what it states on boot) so I figured DOS 1.x would be an ideal OS, particularly since there's a Corona image of it on winworldpc.com.

I found a DOS 3.30 disk and that won't let me format the drive either. :(
 
Dirty way, if you can't get format to work, yet the drive works fine:

Just do a del *.* on each directory. Then RD the directory. If you need to ensure deletion, copy over files to completely fill up the hard drive, then delete again.
 
Upon further investigation, I'm not sure I'm even accessing the drive, as typing DIR in A and B both appear to give the same output and C can't be accessed.

I've begrudgingly opened the machine to see if I can find anything amiss, and everything appears to be fine. (It's using a rebranded Western Digital hard drive controller)

I may end up removing the hard drive and controller entirely.

Does anyone have access to a manual for this machine so I can check the DIP switch positions on the mainboard?
 
If the machine arrived with the drive installed already I wouldn't start messing with settings as they are likely already set.
Have you booted 3.3 and checked what fdisk had to say about the drive, or used DEBUG and checked to see if you could invoke the ROM LLF utility?
 
If it didn't boot from the hard drive in the first place, the drive or controller is probably dead.

You will need to find the exact model of the hard disk controller card, perhaps post a picture of the controller. I'm guessing the card is IBM PC compatible, and was probably added to the machine.

Were there any hard drive related errors during power up?

If you just need to wipe it, the easiest thing is to preform a low level format.

Start DEBUG and enter "G=C800:5". That typically will start a low-level formatting program, although some controller cards were different. If that completes successfully, then run FDISK followed by DOS format.
 
I ran DEBUG > G=C800:5 in DOS 3.30, and the drive's activity LED finally activated and gave the message "successfully formatted the drive". :D

But typing "C:" still results in "invalid drive specification"

How can I install DOS to the hard drive, or copy the contents of a DOS floppy to it if the drive letter is invalid?
 
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Have you tried FDISK after you did the low level format with DEBUG? That will create a partition that FORMAT will then be able to turn into an usable C: drive.
 
Fire-Flare said:
I ran DEBUG > G=C800:5 in DOS 3.30, and the drive's activity LED finally activated and gave the message "successfully formatted the drive". :D

But typing "C:" still results in "invalid drive specification"

How can I install DOS to the hard drive, or copy the contents of a DOS floppy to it if the drive letter is invalid?
Click to expand...
The next step would be FDISK, but if that reports there is no hard disk present then it probably means the hard disk is dead.

Note that BIOS low level formatters like this one do not verify that the low level was written correctly, only that the drive goes through the seeking motions.

However, one thing to double check is the smaller data cable that connects from the controller to the hard disk. Make sure it is plugged in all the way, not plugged in backwards, and it is connected to the first data header on the controller rather than the second. Then retry the LLF. Any problem with the data cable can also cause the symptoms you see.

(I am still assuming this controller is compatible with the machine it is in)
 
I checked the cables, the data cable is keyed and only goes in one way, and the other cable matches the orientation.

I suspect that the drive truly is dead, or perhaps the motherboard's DIP switches aren't configured correctly. If only I could get a copy of the manual...
 
Or you need special software or have to reverse engineer whatever screwy thing Corona did after replacing the IBM BIOS with an in-house written BIOS. Ah, for the days when I could go to the company storeroom and pull out a retired spare MFM drive to test these types of issues.
 
Good point. Does the Cordata BIOS allow for BIOS extension ROMs? Early 5150 ones didn't. The ROM still appears in memory, but the BIOS doesn't link to it. FDISK wouldn't see that drive in that case, as INT 13H hasn't been "hooked".

If that's the issue, it may be possible to use a little DEBUG script to get it to hook INT 13H.
 
I think you're onto something. Whenever I boot the machine with no floppy it gives me the error "INT 18H - Boot Failure."

What debug script should I type in?
 
Fire-Flare said:
I think you're onto something. Whenever I boot the machine with no floppy it gives me the error "INT 18H - Boot Failure."

What debug script should I type in?
Click to expand...

I'm doing this from memory, so I could have some serious clams, but, AFAICR:

Code: 
DEBUG
-a100
xor cx,cx
mov es,cx
mov ds,cx
call far c800:3
int 3
-g=100
-q
 
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