On 30/06/2020 16:44, Kyle Owen via cctalk wrote:
> Happy birthday to the 370! Looks like it was released to
> the press on 30
> June 1970.
Well, actually, IBM released the first 370 in 1968, only
they didn't want to tell anybody too soon.
So, they camouflaged it as a new 360 model, the /85, and
only sold it to the (US) NSA, so nobody was going to get to
see it for a while.
The 360/85 was a prototype of the 370/165, and they really
didn't change much to make it the 370.
The /85 had 16-bit static RAM for a small writable control
store and storage buffer (cache), as well as a read-only
control store for the 360 instruction set. The 370/168
moved up to 64-bit static RAM chips, and the entire control
store was writable. They also changed the logic cabinet
layout a bit.
The computer console was identical, as far as I can tell,
although photos of the /85 are extremely rare.
The /85 was the first machine IBM delivered with the MST4
monolithic logic chips, storage buffer, writable control
store, water cooling, and probably a few other things.