[syslinux] syslinux-3.50 Physical Floppy Disk Access

[Desmond Boyd]

Desmond Boyd Wrote:

Hello,

I am using the pxelinux.0 and memdisk files from distribution syslinux-3.36.

I am no longer able to access the real floppy disk drive B: instead I just
get a mirrored copy of the emulated floppy disk A:

The default config file is as follows

label 1
	kernel memdisk
	append initrd=kd202.img


I was previously using the sysliunx-3.20 distribution which gave me access
to the real floppy disk drive using drive B: with Emulated Floppy Disk as
Drive A:.

Do I need to add any additional switches to the append line to enable the
latest version to enable me to access the real floppy disk drive?


H. Peter Anvin Wrote

That should still work.  I don't know why it would be broken for you now.

lease try the intervening versions, including prereleases, so we can
figure out where it broke.


Desmond Boyd Wrote:

As requested, I have tested the distributions listed below to try to isolate
when physical disk drive access for me was lost, results are as follows:

Physical Disk Drive B: OK with Virtual Disk Drive as A:
3.20
3.30
3.31
3.32 Pre1

Physical Disk Drive B: Not Present only Virtual Disks A: and B:
3.35
3.35 Pre1
3.35 Pre2
3.35 Pre3
3.35 Pre4
3.35 Pre5
3.36
3.50

H. Peter Anvin Wrote

It seems to be a problem with memdisk as I also tested each memdisk version
with the latest pxelinux.0, so currently I have in the tftpdroot:

Pxelinux.0 Version 3.50
memdisk Version 3.32

This combination gives me access to the phyical floppy disk b:

Could you also test the various 3.32-preX releases (2 to 8) to narrow
down the failure further?

The most likely failure seems to be between 3.32-pre3 and -pre4:

    memdisk: Constrain input drive numbers both by equipment byte and
    INT 13h

    Apparently on some BIOSes, INT 13h return a bogus number of floppy
    drives when the real value is zero (probably because the code
    doesn't check the validity bit in the equipment byte.)  Do it
    ourselves if we need to.

There should be a line when MEMDISK boots up saying something about "INT
13 08", what is that printout?


Desmond Boyd Wrote:

Version 3.32-pre3 Physical Disk Drive B: OK with Virtual Disk Drive as A:
Version 3.32-pre4 Physical Disk Drive B: Not Present only Virtual Disks A:
and B:

INT 13 08 Success, Count = 1, BPT = f000:a137
old int13=f00023cb, int15=f000f859
new int13= 9ec00008, int15=9ec00375

All memory addresses listed on the memdisk info page @ bootup for pre3/pre4
are identical but pre4 does not see the physical floppy disk.

If you need the exact screen information from both versions I can write each
one down unless there is a way to save the boot information with a switch to
the virtual fdd then I can upload the info to a networkshare.


Desmond Boyd Wrote:

Any luck on fixing the floppy disk access problem or is it only affecting
me?


Geert Stappers Wrote:

Test reports of newer versions then 3.36,
such as the recent released 3.50, are welcome.


Geert Stappers
Annoyed about a thread posting not belonging in the thread.


Desmond Boyd Wrote:

I did all the tests as far as im aware, there listed in the previous posts,
if theres anything else i need to do please let me know.

Geert Stappers Wrote:

Things to do:

- Be aware that you are addressing a community.
- Find common interrests in that community.
- Convert a personal/private problem in a community challenge.
- Be carefull with other peoples time.
- Make good (as is usefull) references to previous postings.
- Reply below the text.
- Keep smiling!


Cheers
Geert Stappers


Desmond Boyd Wrote:

I am sorry if i have not posted any previous messages in the correct thread 
but this is the first time using this type of email support system.  I 
thought i had to reply to the thread with the origional topic header to 
enable it to be filed correctly.

I have put all previous messages in this email and hope that this is what 
you required.

_________________________________________________________________
The next generation of Hotmail is here! http://www.newhotmail.co.uk