[Coco] Backup of HDB-DOS drives
robert.gault at att.net
Tue Jan 17 07:37:51 EST 2012
Jim Hickle wrote:
> I'd like to backup HDB-DOS drives from one device to another. I have SCSI drives. Perhaps I could use BACKUP in a loop but don't know if it's possible for HDB-DOS to address two different devices.
> I'm thinking of using NITROS9 with a device descriptor set up for source and destination HDB-DOS, open each as a raw device, and copying 256 * 35 * 18 bytes. Do we have a program like Linux's 'dd' ?
The Ken-Ton scsi interface used with the RGBDOS system could only address one
scsi device at a time. I'd be surprised if the Cloud-9 interface is
significantly different in this regard. As a result of the hardware limitation,
RGBDOS could not copy or backup directly from one scsi drive to another.
Bruce's suggestion of using an intermediate RAM drive (if you have 512K RAM)
is a good one and about the only thing that will work with RGBDOS (or I suspect
As Gene indicated, using OS-9 to backup HDBDOS drives needs to be done
carefully to avoid errors generated by changing LSN0. Whether you run into this
type of error will depend on the driver you use to access the HDBDOS drives.
Written correctly, the driver should only see LSN0 of the OS-9 partition for
the two scsi drives. The HDBDOS drives will be accessed using a sector offset
value so there would not be a change to the LSN0 values. With this scheme, you
would need a custom track copy program, Backup would not work.
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