Subject: Re: DVD-RAM: geometry & hangs
To: None <hubert.feyrer@informatik.fh-regensburg.de>
From: Rolf Grossmann <grossman@securitas.net>
List: tech-kern
Date: 11/17/1999 00:41:06
Hi,

on Tue, 16 Nov 1999 21:45:17 +0100 (MET) Hubert Feyrer wrote 
concerning "DVD-RAM: geometry & hangs" something like this:

[...]
> sd1 at scsibus targ 4 lun 0: <MATSHITA, PD-2 LF-D100, A113> SCSI2 5/cdrom removable
> sd1: could not mode sense (4/5); using fictious geometry
> sd1: 595MB, 595 cyl, 64 head, 32 sec, 512 bytes/sect x 1218960 sectors
[...]
> It seems the faked gemometry is a bit strange. The size should be
> something at 5.2GB, and two heads.

I have the same drive here at work (and we're successfully using it with
on a BSD/OS 3.1 machine, but that's not the point). I don't think that this
drive has 2 heads, though, because I can't specify a geometry that would
amount to 5.6 GB, but flipping the disk and using two sides works just fine. 

This is the disklabel I'm using:

# sr0:
type: SCSI
disk: MATSHITA PD-2 LF
label: 
flags: removable
bytes/sector: 512
sectors/track: 64
tracks/cylinder: 8
sectors/cylinder: 512
cylinders: 2381
sectors/unit: 4875840
replacement sectors/track: 0
replacement sectors/cylinder: 0
alternate cylinders: 0
rpm: 3600
interleave: 1
trackskew: 0
cylinderskew: 0
headswitch: 0           # milliseconds
track-to-track seek: 0  # milliseconds
drivedata: 0 

Bye, Rolf