🚀 go-pugleaf

In article <1990Oct9....@spcvxb.spc.edu> te...@spcvxb.spc.edu (Terry Kennedy, Operations Mgr) writes:
>  Does anyone remember the IBM "Data Cell"? It was introduced around the
>same time as the 360, as I recall. Imagine a cross between flypaper and
>a tie rack 8-). It used long strips of (maybe) 2" tape and would go fondle
>the desired strip onto the read/write station on demand (or maybe after
>being repaired). Standard procedure was to read the full tape set once per
>shift, or the beast would start sticking with disastrous results.

There were 8 "bins" on a data cell, each of which held some large number of
tape strips. The bins were shaped and arranged like slices of pie; the
"pie" was rotated to bring the correct bin to the "pick" mechanism that
(if you were luck) pulled out the tape strip.

You couldn't run the data cell without 8 bins; you _could_, however, 
replace a bin with a dummy bin, filled with sand, to keep the whole
mess balanced.

The vestiges of the data cell live on in the 8 byte "full disk address"
used by MVS:

	M BB CC HH R
	| |  |  |  |
	| |  |  |  +--- record
	| |  |  +------ head
	| |  +--------- cylinder
	| +------------ bin
	+-------------- extent

The successor to the data cell was the 3850 Mass Storage System (MSS).
The MSS contained a honeycomb structure filled with spools of tape
in containers that look for all the world like beer cans. A "truck"
would run around over the honeycomb, pick the right spool and mount it 
on a read/write mechanism, which "staged" the data onto a 3330 disk.
These suckers aren't sold anymore, but I'll bet someone still has one
in service.

Aren't widgets wonderful?

-- Jerry Callen
   jca...@encore.com