[syslinux] MEMDISK issue with OptiPlex GX280,620

Gene Cumm gene.cumm at gmail.com
Tue Jan 25 19:07:15 PST 2011

On Tue, Jan 25, 2011 at 18:40, Jason Vasquez <jvasquez at kennesaw.edu> wrote:
> Good day to you, too. No worries about the delay. I understand how busy everyone is with SYSLINUX. Gladly, the project continues to develop and improve. With that said, thanks for today's flurry of activity regarding my reported problem.
> Impressively, the debug version of MEMDISK that you had directed me to use appears to have done the trick. Results below.
> command line: initrd=images/misc/c.img pause BOOT_IMAGE=memdisk_memdskprobedbg
> Disk is hd0, 10404 K, C/H/S = 306/4/17 (MBR/MBR), EDD on, rw
> Using safe INT 15h access to high memory
> Code 1744, meminfo 276, cmdline 66, stack 512
> Total size needed = 2598 bytes, allocating 3K
> Old dos memory at 0x9fc00 (map says 0xa0000), loading at 0x9f000
> 1588: 0xffff  15E801: 0x3c00 0x7dc3
> INT 13 08: Success, count = 1, BPT = 0000:0000
> Drive probing gives drive shift limit: 0x82
> old: int13 = f0005c6f int15 = f000f859 int1e = f000efc7
> new: int13 = 9f00000a int15 = 9f0003ba int1e = f000efc7
> Loading boot sector... press any key to boot...
> No 'lost drive' message was reported and the internal hard drive is now visible to the booted environment. I also tried (only on the OptiPlex GX280, at this time) this debug version with my Ghost client image from previous trials, and it works. Yay. So does this mean the genius team has fixed the issue? I can perform further testing, but the latest changes look promising indeed. Much thanks.

One part, yes.  I've got an E6400 with A14 that still "lost the last drive".

Loading from a USB flash drive (my build at 558087b):

INT 13 08: Success, count = 2, BPT = 0000:0000
INT 13 DL80:
 AH08: CF0 BL00 DL02
 AH15: CF0 AH03
 AH41: CF0 BXaa55 AH21 DH00
BDA drive 80? 1, total count: 2
Press a key to continue...
INT 13 DL81:
 AH08: CF0 BL00 DL02
 AH15: CF0 AH03
 AH41: CF0 BXaa55 AH30 DH00
BDA drive 81? 1, total count: 2
Press a key to continue...
INT 13 DL82:
 AH08: CF0 BL00 DL02
 AH15: CF0 AH01
 AH41: CF0 BX55aa AH01 DH00
BDA drive 82? 0, total count: 2
Press a key to continue...

The results on DL=83h through FFh are identical to 82h.

I'm also trying to make a different FreeDOS image as the default has
some partition errors and causes more trouble with some machines.


> ----- Original Message -----
> From: "Shao Miller" <Shao.Miller at yrdsb.edu.on.ca>
> To: syslinux at zytor.com
> Sent: Tuesday, January 25, 2011 5:23:34 PM GMT -05:00 US/Canada Eastern
> Subject: Re: [syslinux] MEMDISK issue with OptiPlex GX280,620
> On 1/25/2011 16:38, Shao Miller wrote:
>> On 1/25/2011 13:36, Jason Vasquez wrote:
>>> Gladly yes to test, thank you.
>>> System used: OptiPlex GX280, BIOS A08. Results below.
>> ...It's the bogus AH == 0x15 "success" case that's hurting these
>> models.  I will address that and submit another patch.
>> Thanks for testing.
> Good day again, Jason.  Would you be so kind as to please test:
> http://git.zytor.com/?p=users/sha0/syslinux.git;a=blob;f=memdisk/memdskprobedbg;h=ae4d6188d8ba7c8b435abb9749501167eb5356c4;hb=25bd5be054ff1bfac7c2dc2f1a92d44e60cd437e
> Apologies for the delay.
> - Shao Miller

More information about the Syslinux mailing list