Status update, plus need HP 790x disc drives

From: Jay West <jlwest_at_tseinc.com>
Date: Wed Jun 2 13:52:59 1999

I'm also posting this response to classiccmp in case others are interested
in some of the details....

You wrote...
>Eek! COOL!! What media did you locate the software on? Is it running
>(or soon to be) on your 1000F's?


The media is still in transit, I haven't got it yet. He said it was on 7900A
disk cartridge, but he might also send it on 1/2 tape. It will start out
life running on two 2100A's. Then it will migrate to either my 2109B/2113B
or if that fails the 2117F's. Eventually it will also run on a Unix or
DOS/WIN PC via an emulator.

>Aargh! What is the capacity of a 7900A? Does the "Access" version
>require (shudder) a drum?


The 7900A is 5mb (2.5 fixed, 2.5 removable). The 7906 is 20mb (10 fixed, 10
removable). Only the very earliest versions of TSB used a Drum; since the
Access version is the last version of TSB ever made, it will run fine
without a drum (probably can't use a drum either). Even if I ever got a drum
unit, I think that would be beyond my capabilities to repair.

>So, for reference; what are the capacities (and form factors) of the
>listed drives? For that matter, what are the interface types? Are there
>third party equivs?

The 7900 uses a 12940 cartridge. This is a single platter, 24 hard sector
cartridge. It has a raised area on the top that opens to accept the heads
when inserted into the drive. From what I understand about RK05's, the disk
cartridge is mechanically/cosmetically similar. The 7906 uses a similar
cartridge (12989), but there is only one sector notch on the hub instead of
24. The 7920 (which I'm not really familiar with) I think used a 10 platter
top loading cartridge. PS - I might have 12940 and 12989 interchanged
above - poor memory :) Also, I don't recall the mils measurements, but the
internal media platter is a different thickness between the 12940 and 12989.

The 7900 drive hooked up to a 13210 controller in the cpu backplane. You
could daisychain 3 more drives off the main 13210 controller.

The 7906 used a different arrangement. In the cpu backplane was a 13037
card, which went to a rackmount box called a 13037 disc control unit (about
5 inches tall). Cables from the 13037 went to each 7905/7906/7920 drive.
ISTR that the 13037 disc control unit (rev C at least) could support up to
eight drives, and could support two separate computers. It also supposedly
supported HP-IB drives too (but I don't think TSB would use the HP-IB
drives, even through the 13037).

>No, can't have that! Redundancy and all!! 'Off-site archive?' B^}


I haven't settled on which systems I'll run it on yet (2100, 21MXE or
21MXF), Because I haven't, I will likely have some equipment left over from
my scavenging. If so, it will be offered on classiccmp.

>Aargh II! I'll try shaking some bushes around here and see if anything
>falls out.


Mucho Appreciation!

Jay West
Received on Wed Jun 02 1999 - 13:52:59 BST