Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 30 Dec 1996 16:14:33 -0800 (PST)
From:      John-Mark Gurney <jmg@nike.efn.org>
To:        Joerg Wunsch <joerg_wunsch@uriah.heep.sax.de>
Cc:        freebsd-bugs@freebsd.org
Subject:   Re: bin/2303: cdcontrol can read to many toc entries if track numbers are large
Message-ID:  <Pine.NEB.3.95.961230154328.296k-100000@hydrogen>
In-Reply-To: <199612301547.QAA04285@uriah.heep.sax.de>

next in thread | previous in thread | raw e-mail | index | archive | help
On Mon, 30 Dec 1996, J Wunsch wrote:

> As John-Mark Gurney wrote:
> 
> > > I leave it to others to see whether your patch is ok or not.  However,
> > > this CD does IMHO violate the specs.  There must be no more than 99
> > > tracks on a CD.  So better complain at their producer. :-)
> > 
> > but there aren't more than 99 tracks...  there are exactly 99 toc
> > entries...  and the track numbering happens to go above 99...  attached is
> 
> Eeeek.  What a horrible abuse.

[write a message, the with some new testing the following comes out:]

gak!!!  I found the real problem....  it's the cdrom drive...  the drive
that I use to play audio cd's is CHINON CD-ROM CDS-535 Q20...  I just
tried to read that same cd on a PLEXTOR CD-ROM DM-XX28 3.08... and it
reports that correct number of tracks (1-99)...  

[and some more testing:]

ahhhh.... it turns out that the chinion reports packed BCD numbers...  I
thought it was funny that two cd's both with 99 tracks would report 153...
but if you convert 153 to hex you get 0x99... i.e. 99 tracks... hmm..
looks like I'll finally go and see if I can get a fireware upgrade for my
two chinon drives...

[now thinking about the problem:]

hmm... should a fix like this go into the driver?  i.e. an option that
will convert bcd -> binary, and back for interaction with the drive...
then enable it with a quirks entry?

so would the above be the proper fix?  as far as I can think it should
be...  of course I don't know the scsi code that well.. but if it is... I
will see what I can do about adding the option...

> > results from "echo info | cdcontrol > brk" to give you a list of the
> > tracks to see that there aren't more than 99...
> 
> I wonder why they didn't get the idea to name one of their tracks
> `170'. :-))

well..  the above explains this :)...  ttyl...

John-Mark

gurney_j@efn.org
http://resnet.uoregon.edu/~gurney_j/
Modem/FAX: (541) 683-6954   (FreeBSD Box)

Live in Peace, destroy Micro$oft, support free software, run FreeBSD (unix)




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.NEB.3.95.961230154328.296k-100000>