HP 85 & a bit more.

From: blstuart_at_bellsouth.net <(blstuart_at_bellsouth.net)>
Date: Tue Mar 16 19:50:51 1999

In message <3.0.1.16.19990316212916.3bef20fe_at_intellistar.net>, Joe writes:
>At 10:50 PM 3/16/99 -0000, you wrote:
>>> They're made for the old 3M DC-1000 tapes, DEC tapes work great.
>>
>>No, I've tried DECtapes. It takes a lot of force to get them into the
>>slot, and they don't seem to work. :-)
>>
>>For the uninitiated, DECtapes are six-inch reels of 3/4 inch (?) tape.
>>
>>I think Joe is saying that the 85 needs the same cartridge tapes as the DEC
>>TU58 "DECtape II" drive, as commonly found on the PDP-11/44, VAX-11/750, and
>>other early-80s DEC machines. Despite the moniker, there is almost
>nothing in
>>common between DECtape and DECtape II.
>
> You may be right about the DEC stuff but the tapes that I have (about 20
>of them) only say DECtape and they definitely fit the 9815, 9825, 9915, 85,
>etc.

A couple of points:

On the almost nothing they have in common... Physically, they
don't, and they don't really have much in common in terms of the
tracks on the tape. But they've got a unique feature in common.
They are used in a way that are block addressable, like a disk.
In fact Thompson's first UNIX on the PDP-7 used the original
DECtape as it's primary storage.

On the use of DECtape IIs for the HP-85 and 9800 series... Please
don't. As much as I love my HPs, I desperately keep any DECtape IIs
I have for use with DEC stuff. The DECtape IIs are formatted at
the factory and I know of no way to format them with controllers
in the field. (I'd love to be proved wrong about that, BTW.) So
I (and I'm sure others) would be grateful if DECtape IIs could be
saved for use with TU-58s.

Brian L. Stuart
Received on Tue Mar 16 1999 - 19:50:51 GMT