China DOS Union

windrv:

Is that so? Can grldr be used in non-emulation mode? How did you do it? You must share it with everyone! So, that means stage2_eltorito can be dispensed with, right?

To Gandalf :chainloader (hd0,0)/ieldrIf it is loaded by boot.ini with grldr, then the ISO can be booted. If it is grldr (or stage1, stage2) on a floppy disk, then when booting the ISO, a CPU protection error occurs and it restarts automatically!

According to what gandalf said:
- The IELDR uses the basic structure of grldrstart.S + isoemu. When grldrstart.S places the main part of isoemu at 0x0000:0x8200, the code of the main part of isoemu will first move the entire isoemu to another address to run... ; )
From this, it can be envisaged that the following boot method is more perfect than the previously mentioned method chainloader (hd0,0)/ieldr:
chainloader --load-segment=0x2000 --load-offset=0 (hd0,0)/ieldr
Among them, the value of --load-segment can also be 0x1000 or 0xd00.
Please use this boot method.

I tried, but still couldn't boot the ISO from menu.lst on the floppy disk. Although it's exactly the same as the item in menu.lst on the hard disk, the former will have:
Loading Stage2 from the CDROM......
An random processor error occurred.
This PC automatically restarted.
Note: (hd0,0) all have ieldr, isoemu.ini, cdrom.iso. And the content of isoemu.ini is isoemu cdrom.iso
title Boot from iso file (hd0,0)/cdrom.iso
chainloader --load-segment=0x1000 --load-offset=0 (hd0,0)/ieldr
As long as you select the above item from the grub installed on the hard disk - whether it's grldr loaded through boot.ini or root(hd0,0) setup(hd0,0) - in menu.lst, it can boot the ISO normally.
But as long as you select the above item from the grub installed on the floppy disk - whether it's guided by grldr or root(fd0) setup(fd0) - in menu.lst, it will have the automatic restart described at the beginning.

Solving the above problem is of great significance! Because if it can be solved, I can make the computer boot from a bootable ISO on the hard disk with just one floppy disk. (The method is in post 92) I hope Gandalf and Brother Budian will work hard to solve it, and I will continue to be the most faithful tester.

Experts are all here to cheer! Hehe, so excited

TO BLUE777:
Please test the floppy boot ISO with my attachment. This floppy IMG might be the smallest FREEDOS I've ever seen...Open the attachment

It can be put into your GRUBDISK and called with MEM for this IMG. Since it is only 57K, it should not have a big impact on the space of your tool disk, right?

I already had this before. In the floppy boot disk I made with syslinux boot, the dm.gz compressed image uses it as the kernel. Among them, command.com is actually the miniCMD of ROM-DOS. And kernel.sys is an early kernel of Free-DOS. But I still thank your reply. I will feed back in time after testing.

According to blue777's description, it seems that there might be something wrong with ieldr itself. But I can't be sure because grldr might also cause this problem. However, I don't seem to be able to find where there's a problem with GRLDR at the moment.

Now I'm not making GrubDisk boot disks anymore You can also take a look at the latest boot disk I made with sysliux + grub dual boot, I think it's pretty good. There's a download in the "Pandora's Box" directory at http://bootdisk.ys168.com.

To hnlyznd:
The latest test results confirm Brother Budian's guess: "ieldr itself may have an issue", because the latest ieldr.exe you provided that claims to support MS-DOS 3.30, FreeDOS kernel 2032 and later versions is used under pure DOS. (The image you uploaded I have tested, and ieldr.exe is not supported.) While I tested with pure MS-DOS 7.10 real mode (only kernel io.sys + command interpreter commander.com), ierldr.exe still has the error I described in "Post 124".
Therefore, only the ieldr author can solve the problem of "cannot call (hd0,0) ieldr from menu.lst on floppy to boot ISO" — although this is a very puzzling bug.

No, that's not right. The IMG I tested can start completely. Is there a problem with your test environment? Also, if you have protection software or a protection card installed, it will cause a startup failure. If you don't believe it, I can post pictures for you.

Please post a few pictures for me to refer to, and upload a video I tested for you to see:
Change the extension .zip to .exe to watch it directly, because the forum does not support uploading .exe files.
Open the attachment

The above is the video of grub running the image through memdrive. The following is the video of me directly running the image you gave. ieldr.exe can run, but the error I mentioned still appears. (Change the extension .zip to .exe to watch)
Open the attachment

Look, I'm using VPC to boot, and I made a few pictures during the boot process. I don't know if it can explain the problem.