On 2016-05-24 4:13 PM, Chuck Guzis wrote:
On 05/24/2016 11:39 AM, Eric Smith wrote:
On Tue, May 24, 2016 at 12:25 PM, Paul Koning
<paulkon...@comcast.net> wrote:
On May 24, 2016, at 2:07 PM, Chuck Guzis <ccl...@sydex.com>
wrote: ...and the "transformer" ROS used on the 360/40 (and
others).
You mean "Core rope memory"?
IBM's TROS and Core Rope Memory use the same principle, but the
physical construction is significantly different. Core rope memory
was very labor-intensive to manufacture, while TROS was not.
There's a photo here;
http://www.cs.sun.ac.za/museum/memory.html
I seem to recall that reworking the 360/30 microprogramming was
preferred by tinkerers over the 360/40 was primarily that CROS was
easier to work with than TROS.
I don't recall what the RCA Spectrolas used.
--Chuck
The CROS cards used in a 360/30 where the same size as an 80 column card
on purpose so you could you a keypunch machine to program the microcode.
