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Hi all,

Hopefully i'm not asking something that's been answered, i've looked around for the answer but without success.

here's the tl;dr: I have a folder containing a complete 20MB hard drive that I want to make into a chd for Mess.

I've yanked all the data from an old WD-25 MFM drive through a straight copy, and was hoping to make a chd out of it to use with MESS. It's from an IBM XT that I had as a kid. Any ideas on whether this can be done? I'd like to create a chd directly from the drive itself, but to get the data off, I had to boot from a DOS floppy, and xcopy to a zip drive, so having this folder is my only real option right now. I have access to both Windows and Linux (for dd or tar) if that helps or is needed.

thanks in advance.
First I would create a .chd file of the appropriate size using chdman. Next I would add the files to the chd using imgtool. ex:

chdman -createblankhd blank.chd 306 8 17
(This creates a 25 MB image file I think)

imgtool put pc_chd blank.chd <nameofyoursourcefile> <nameofthedestinationfile>
(This "puts" files into the image one at a time)

I may have ommitted something here because I am in hurry to get back to the phone (it rang while I was typing this!) smile If I can be of more help let me know.
thanks for the quick response! OK, so I didn't read the help of chdman enough! I was able to create a hard drive (306,4,17 are the CHS for the original):

chdman -createblankhd xt.chd 306 4 17

but the following error occurs:

imgtool.exe put pc_chd xt.chd ..\MFM\ADMSMTH.DOC ADMSMTH.DOC

xt.chd: Corrupt image

So, I started using wimgtool.exe which created a similar disk; 100/16/32 or something like that. wimgtool.exe is sort of buggy in it's copies, but dragging and dropping is a whole lot better than one at a time copies (although i was kind of looking forward to scripting it!). I copied the system files (DOS3), autoexec, config.sys, command.com and the DOS directory (I did not see IO.sys or msdos.sys....it's been a while, but shouldn't those be there with DOS3.x?)

upon starting MESS, I'm getting all sorts of disk controller errors as before (601, 1701 depending on the model).

Do I need to format the chd at all? mark it as an active partition?

thanks again for all the help?

oh, and I'm using 0131 of Mess, as i read that later versions had issues with PC chd's.
I would think that you would need to partition it...
I tried running fdisk inside the emulator and that hung and never returned...
Your best bet would be to fdisk, format, and SYS the drive from inside MESS using a boot disk of the appropriate DOS version, and then copy over your data files afterwards. If you just copy msdos.sys etc. it won't work because they won't go into the right sectors.

Personally I don't use imgtool/wimgtool for working with CHD files because it's pretty buggy, I copy files a few at a time to floppy images created with WinImage and then copy them inside the emulation. This would be kind of a pain for a whole hard drive's worth of files though.

The PC hard drive code also has some issues at the moment so I'm not sure if everything would work even if you did it all exactly right.
Booting the old style...

First you need to partition your hard disk and make your partition active. using FDISK. The BIOS will look for this partition.

Later you need to format your partition with the /S option, not all the DOS versions support this switch.

Otherwise you could format your hard disk and next execute SYS c: this will copy IO.SYS, MSDOS.SYS and COMMAND.COM and point the first sector of the partition to IO.SYS.

You need to do this to been able to boot from the hard disk, if you just copy the files it will not boot.
Ok, So, how do you get around fdisk hanging? I'll try it on my Mac and see if I have better luck there...
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