Re: Announcing cdrskin-0.4.4

["Thomas Schmitt" <scdbackup@gmx.net>]

Hi,

>  READ FORMAT CAPACITIES:
> - unformatted:      12219392*2048=25025314816
> + formatted:        11826176*2048=24220008448

Ahum. Looks really like initial formatting is needed.

I had a look into dvd+rw-format.cpp.

  fprintf (stderr,"- you have the option to re-run %s with:\n"
                  "  -format=full  to perform (lengthy) Full Certification;\n" 
                  "  -ssa[=none|default|max|XXX[GM]]\n"
                  "                to eliminate or adjust Spare Area.\n",
                  argv[0]);


It seems you could make an experiment with format 31h
(i.e. no spare area) by dvd+rw-format option
  -ssa=none

It might also be worth to check the impact of certification
on write error detection. I.e.:
  -format=full

I understand from MMC specs that certification is a read
process which evaluates the quality of data recording and
eventually records bad spots in a list. It is unclear to me
whether this list resides permanently on media.
But if we are lucky, the drive trusts the certified blocks
and refrains from reading them after write.
If we are a bit less lucky, then we need command WRITE12
rather than the usual WRITE10.

Hopefully the formatting will not damage the only media
you have. :)

I would propose to try both. It would be most economic to
do  -ssa=none  first, because i would expect it to be
the most likely to omit error detection on traditional
WRITE10 (SCSI command 2Ah).

With  -format=full  i would possibly expect that WRITE12
(command AAh) is needed.
There seems to be a WRITE12 experiment ready in
dvd+rw-tools-7.1/growisofs_mmc.cpp

Maybe Andy Polykov already knows more about that topic.
Andy ? Are you reading this ?


Have a nice day :)

Thomas