Odd PDP-11 tape related question

From: Zane H. Healy <healyzh_at_aracnet.com>
Date: Tue Jan 13 15:54:23 2004

> Beware that *many* DDS1 drives cannot do variable-sized blocks very
> well... if memory serves me right, RSTS BACKUP format uses many
> block sizes in a single backup file:
>
> 80 - ANSI header
> 14 - RSTS file header
> 1024
> 2048\__ data block sizes, often +4
> 4096/
> 8192
>
> This might be your problem.. even though the tape image is
> fine, the drive doesnt let you use arbitrary block sizes.
>
> This may or may not apply to your drive.. Nico might know
> more about this- I just ran into this when writing an ASPI
> layer for my software... I was unable to tell the DDS drive
> to switch to 64-byte blocks.. it insisted on 512-b blocks.

Interesting.... BTW, the DDS1 drive I'm using is a DEC TLZ06. Any idea if
this might also be a problem with an Exabyte 8500 tape drive? It would be
easier for me to attach an Exabyte 8500, than it would be to get a TZ30
hooked up. Well, maybe not that much easier, I think all the tapes are
buried in the same spot :^/

                        Zane
Received on Tue Jan 13 2004 - 15:54:23 GMT