10 Apr
2024
10 Apr
'24
3:17 p.m.
On 4/10/24 01:51, Van Snyder via cctalk wrote:
On Tue, 2024-04-09 at 22:21 -0700, Chuck Guzis via
cctalk wrote:
The 360/20 had only halfword instructions, no float, no char
strings. But, main storage was 16 bits wide.
The 360/30 only had byte-wide memory, and the register file
was in a separately addressed part of main storage. The
360/25 was a very interesting concept. The microcode was in
the top 16 KB of main storage, and 360 and other instruction
set emulations could be loaded from cards. The boot loader
for the emulators was in the top 16 bytes (or maybe words)
of main storage.
Jon
On 4/9/24 22:03, ben via cctalk wrote:
I don't
remember whether it was one of the docents at Haus zur
Geschichte der IBM Datenverarbeitung at Sindelfingen, or at the
Computer History Museum at Mountain View, who told me that IBM was
developing a machine to be designated 1480, as part of the 1401-1440-
1460-1410 series, with newer technology, roughly contemporaneously with
the 360. When IBM decided to put all its eggs in the 360 basket, The
1480 team somehow survived and produced either the 360/20 or 360/25. An
8k machine would be a bit weird in this series, since 1410 was already
100k. Does anybody know more details about this? On 2024-04-09 8:53 p.m., Murray McCullough via
cctalk wrote:
What model of a 360? 8K
sounds a lot like a Model 20, which the
purists
may not consider to be a "real" member of the family. I had not realized the IBM 360 was 60 yrs. old
this month. I
worked on
such
a computer in the late 60s in Toronto. What one could do with 8
Kbytes of
ram was remarkable!
Happy computing
Murray 🙂
Real time sharing, not a 16K PDP 8?