Re: is my drive defect - request for comments

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

Hi,

Helmut Jarausch wrote:
> I tried PLATINUM and VERBATIM media.
> This seems to be connected to this burner (and its
> predecessor LG GH20NS15)
> I have two PC (both AMD 64 running a recent Linux
> system with an 2.6.26 or 2.6.28 kernel)
> Both show this problem (with cdrecord only).
> I managed to burn the CD with cdrskin,

This is a surprise.

Two media brands and two burners
are quite beyond the doubt that this
all is white noise from a mad drive.

It must be some prelude command of
cdrecord which confuses the drives.
Or is it the write block size ?


Helmut reported:
  cdrecord: Input/output error. write_g1: scsi sendcmd: no error
  CDB:  2A 00 FF FF FF 6A 00 00 1F 00
  Sense Code: 0x30 Qual 0x05 (cannot write medium - incompatible format)

which means that 31 blocks were about
to be written to LBA -150 for a SAO
start.
The negative address is correct.
But maybe the drive would prefer to
get 16 or 32 blocks per WRITE.

We saw problems with DVD+R DL after
the first layer was done.
Could this be a new kind of odd
consequence of the write buffer size ?

libburn writes 16 blocks for CD and DVD,
32 blocks for BD.

----------------------------------------------------

Helmut Jarausch:
> cdrecord even failed to burn a DVD on those machines,
> while growisofs succeeded.

Afaik, growisofs sends 16 blocks per WRITE command.

I think we got a suspect now.

Maybe Joerg knows a way how to influence write
buffer size with cdrecord. So Helmut can do a
test ?


Have a nice day :)

Thomas