Writing emulators (was Re: VCF PNW 2018: Pictures!)

[Rich Alderson]

From: Guy Sotomayor Jr
Sent: Wednesday, February 21, 2018 11:24 AM

>> On Feb 21, 2018, at 10:59 AM, Paul Koning via cctalk <cctalk at classiccmp.org>
>> wrote:

>> Typically you'd emulate the I/O device functionality, regardless of whether
>> that is implemented in gates or in co-processor firmware.  That's the
>> approach taken with the MSCP I/O device emulation in SIMH, or the disk
>> controller emulation in the CDC 6000 emulator DtCyber.

> It’s also what’s done in Hercules (S/370, 370/XA, 390, Z simulator) and the
> mainframe I/O is complex to say the least.

Also the method used by the KLH10 emulator (KS-10, KS-10/ITS microcode, KL-10).
There, each device type runs in a separate fork, using System V style memory
mapping.  This of course means that it only runs under certain Unix variants.

                                                                Rich