[Simh] HP2100 - 12821A

[J. David Bryan]

Lyle,


On Thursday, June 20, 2013 at 23:37, Lyle Bickley wrote:

> Unfortunately, SIMH currently does not support CS/80 drives connected
> to a 12821A interface.
> 
> 1. Has anybody already looked at what it would take to do this?

Yes.  For 3.9-0, I added the 7906H/20H/25H ICD drives interfaced via the 
12821A card.  The intent was to create the framework for subsequently 
adding CS/80 disc and Amigo tape drives via the 12821A interface while 
first leveraging the disc simulation work from the 13037 MAC controller 
discs (hp2100_ds.c).


> 2, Or already has some alpha/beta code written to do so?

No, although there is a future plan to address this.


> If neither of the above - some cursory thoughts as to how one might
> implement this feature...

With an eye toward future HP-IB interfacing, the ICD implementation 
partitioned the simulation into a library of disc functions (hp_disclib.c), 
the generic 12821A interface (hp2100_di.c), and separate "personality" 
modules for the Amigo disc, CS/80 disc, and Amigo tape peripherals (the 
existing hp2100_di_da.c, and the future hp2100_di_dc.c and hp2100_di_ma.c 
files).  Adding a CS/80 disc simulation would be a matter of implementing 
hp2100_di_dc.c and tying it into the disc library and 12821A simulation.

The comments in the files describe the partitioning.  If I may answer any 
additional questions, please do not hesitate to ask.


> Thanks!

You're welcome.

                                      -- Dave