[Simh] IBM System/32 emulator

[h.j.stegeman at hccnet.nl]

Hi,

I am new on this list, but not new with simh.

I assisted Dutch Owen in writing his System/3 model 10 emulator, which I 
modified later to a model 15D emulator.

I have now started a new project: an IBM system/32 simh emulator.

The S/32 has two storages:

- Control Storage:
This storage is 4 kiloword large and contains micro-instructions for the S/3
instruction set emulator and the IOS. (The S/32 CPU is hardwired, not
micro-coded)
These micro-instructions have all a fixed length of 16 bits.

- Main Storage:
This storage is 32 kilobyte and contains the SCP written in S/3 machine
code.

These two storages are in different spaces.

First dilemma: what should be the "main storage" from a simh point of view ?
The CPU executes micro instructions from CS, so imho it should be CS.
With:  sim> e 0-15  the content of the first 16 words in CS should be
displayed.

But what to do with the Main Storage ?.
For this storage I also need a "examine" command.

Adding a CS/MS parameter to the "e" command is an option.
Seperate switch that selects CS or MS (the real S/32 has one) would be the
right option I think.
But how can I troggle (dynamic) between 8 or 16 bit data paths in simh ?

Q1: What is the best way to implement operator panel troggle switches in
simh ?
I need them for:
- selecting CS / MS for display / altering storage.
- selecting IMPL CS or IPL from MS.

Q2: How can I display (with the "examine" command) in simh _bytes_ in Main
Storage mode and _words_ in CS mode ?

Example:
sim> troggle sw to CS
sim> e 1
1: 5246
sim> troggle sw to MS
sim> e 1
1: CE

Thanks for any tips or suggestions.

Regards Henk