[Simh] HP 2100/1000 A-series

[J. David Bryan]

On Saturday, June 6, 2015 at 21:44, Cory Smelosky wrote:

> It seems there's no current SIMH support for the HP 1000 A-series system
> (A900, A990, A600 et cetera) meaning RTE-A (with the ARPA/1000 software!)
> is unfortunately out.

That's correct.


> Looks like enough docs for at least some of the later ones are up on 
> Bitsavers...any plans for implementing these missing models?

Holger Veit <holger.veit at iais.fraunhofer.de> had been looking into doing a 
SIMH A-Series simulator several years ago, but I've not heard what progress 
he made, if any.

Regrettably, relatively little of the existing HP 1000 M/E/F-Series 
simulator could be leveraged for an A-Series simulator.  The base set 
instructions are the same, although the I/O instructions and I/O structure 
are entirely different, and there are a number of new instructions.  Also, 
essentially none of the M/E/F peripherals (disc, tape, terminal 
multiplexers, line printers) were supported on the A-Series, so a whole new 
set of peripheral simulators would have to be written.  An off-the-cuff 
guess would be that reusing the base set would cover maybe 20% of the full 
simulator code.  The other 80% would have to be written from scratch.

On the plus side, the full RTE-A sources, the A-Series microcode, and 
several RTE-A binary releases are available in the HP 1000 Software 
Collection on Bitsavers, so the job is by no means impossible.

                                      -- Dave