Re: [PARPORT] ppscsi and a hp6020es cdwriter partial success


Heather Stern (star@starshine.org)
Wed, 13 Oct 1999 12:39:21 -0700 (PDT)


Douglas Baker wrote:
> I have got a hp 6020es cdwriter working on a pentium 166. using the epst and
> ppscsi modules with kernel 2.2.10. (Single speed only)
>
> There are however, a few problems with the disks it writes. The 6020 can
> read the disks it produces but I have found only one other machine a Dell
> Optiplex with NT that can read the disks I have made. I have tried other
> Linux machines a Sun, SGI and a couple of Windows95 boxes.
 
Well, at least you can be sure that you specified the right device... :)
 
> Is there an option I need to specify when I do either the mkisofs or
> cdrecord step?

Since it looks like the data is fine (you could read it on two systems)
the fixation must be the only broken part.
from your log:
> Fixating...
> cdrecord: Input/output error. philips fixation: scsi sendcmd: retryable
> error
> CDB: E9 00 00 00 00 00 00 00 01 00
> status: 0x2 (CHECK CONDITION)

*if* this is a re-writer (I'm not familiar with the specific model, sorry)
     *and* it's an RW media
then you *may* be able to issue the cdrecord command to only fixate the disc
again, maybe it would do it right this time.

Unfortunately if I recall my physics lessons on how RW media for CDs works,
if any (broken; it claimed "recovery needed") fixate data reached the disc
before, that portion won't be blank, so it won't be writable again, and I'm
not sure how you'd tell it to blank only the fixate area.
 
Since you're getting the error consistently, my theory is that your machine
and the NT box which can read it, are ignoring the fixate area. To test my
hypothesis, try telling cdrecord to write everything, but do not fixate the
disc. You should log no errors, but still get a disc that only the two
systems read. Then you can try seperately fixating the otherwise good disc.

Deeper thought: why would *your* machine ignore the fixate area, but other
Linux boxes have trouble? I wonder if this reason, whatever it is, could be
preventing you from proper fixation? You might try fixating it on another
cdwriter, or parallel plugged to one of the other Linux boxes.

[more logs ellided]
> Hope this is of some use, keep up the good work.
> Douglas Baker

Hmm, to me, your log looked just like it could have been gotten on any
system with a cdwriter; that your SCSI is really a parallel conversion,
I dunno, maybe it's a smidge too slow to be doing the fixate right. If
there's really something wrong in ppscsi that's responsible, I suspect
this may be not deep enough in the bits to show it.

However, I'm not one of the parport programmers, merely someone who's had to
troubleshoot bad CD burns before; I got interested in the parport driver
while fighting with something else, and have been enjoying lurking since.
I figured if for once my knowledge would be useful here I should speak up -
least I can do to help the folks who work so hard on the parport drivers.
Thanks guys!

-* Heather Stern -*- star@starshine.org -*- Starshine Technical Services *-

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This archive was generated by hypermail 2.0b3 on Wed 13 Oct 1999 - 15:54:38 EDT