IBM 360/30 in verilog

Guy Sotomayor Jr ggs at
Tue Jul 12 10:33:19 CDT 2016

POP = Principles of Operations.  It is the 360/370 *bible*.  It describes (in detail) how
the architecture works (including all instructions).  It specifies what are “architectural”
(ie can be counted on by all models) and what are “implementation” specific.

Changes to the POP were *very* restricted…that is, the architecture committee needed
a long and detailed justification for any change to the POP and most didn’t make it in.

TTFN - Guy

> On Jul 12, 2016, at 2:04 AM, Curious Marc <curiousmarc3 at> wrote:
> What's a POP? As long as it emulates all the registers connected to light and switches that might do for me, but I was assuming these would very specific to the CPU detailed innards.
> Marc
>> On Jul 12, 2016, at 5:14 PM, Dave Wade <dave.g4ugm at> wrote:
>> It actually might be easier to produce a generic S/360 clone in FPGA using
>> the POP rather than individual ALU's.
>> Having built a very simple CPU (in VHDL not Verilog) and planning to start
>> on a more complex (Ferranti Pegasus)
>> Of course it wouldn't be cycle accurate, but perhaps that wouldn't be
>> important.

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