System360 Hardwired vs. Microcoded 398
158-168 were new technology ... compared to 155-165 ... especially the faster real memory technology. however, i believe the architecture of the native engines were the same and so the same microcode could work.
155-165 weren't designed for virtual memory and required extensive hardware retrofit to install it in existing boxes.
in the early 70s ... most of my POK visits involved 370 architecture meetings ... and didn't run into many cpu engineers ... other than who might show up in such meetings.
System360 Hardwired vs. Microcoded 401
When I was in school (late 70s) we used a 360-44, and I studied it quite a bit. The 44...
in the mid-late 70s ... i got involved with the cpu engineers working on the 3033 ... i was even invited to their weekly after work events, if i happened to be in town (honorary cpu engineer?).
part of the issue was that 370 (non-virtual memory) was just an interim-stop-gap. the real followon was going to be FS (future system). there was huge resources poured into FS ... and it was finally canceled w-o being announced (and few were even aware of it).
as noted in previous posts on FS ... i didn't make myself very popular with the FS crowd ... somewhat panning their effort (there was this long-playing cult film down in central sq ... and I made the analogy to FS of the inmates being in charge of the asylum).
as in other references to FS, FS was supposedly spawned by the emergence of the 360 control clone market ... example:
System360 Hardwired vs. Microcoded 399
165-ii was a field hardware retrofit of virtual memory hardware to 165s currently in the field...
... aka in above refernece it mentions that 2500 were initially buttigned to the project.
I worked on a project as an undergraduate that created a clone telecommunication controller (reverse engineer the ibm channel, adapt a interdata-3, etc)
there later was a write up blaiming the four of us for spawning the controller clone business.
FS may have then contributed to creating 370 clone mainframe market. Amdahl may have left to form his own 370 company in disagreement over the FS direction-strategy (as opposed to bigger, faster 370).