[Simh] Simulating a GT40

[Lars Brinkhoff]

Timothe Litt wrote:
> If a ROM device is added to the -11, I suggest that:
> a) It be capable of multiple units
> b) each unit with a start address (in I/O space) & length

I was going to do this, but I quickly learned that a SIMH unit can't
have a base address of its own.  All units share the address region
defined by the governing device.

> c) the unit accept "attach <FILE>" to provide the code/data

That's what I implemented.  The file is a plain binary image.

> d) the existing gt40 hack that Mark described be migrated to use the ROM

The hack never existed.  It was suggested but didn't work.

> e) preferably, provision be made for the other functions of a ROM module,
> mentioned below.

I'd be willing to work some more on this ROM device, but I don't know
the verdict from Mark yet whether it's suitable for inclusion in SIMH.

Some devices may need adjustments to be able to read from ROM.  This was
the case with the VT11.