S6100 Design Notes
From Spare Time Gizmos' Wiki
The S-6100 is an S-100 card using the IM6100 PDP-8 CPU. The S-6100 includes special hardware that traps unimplemented PDP-8 IOT instructions to control panel memory and, with sutitable firmware, allows S-100 I/O cards to emulate standard PDP-8 peripherals.