PiDP-11/70_

Hardware	PiDP-11/70 replica by Oscar Vermeulen
Emulator	SimH PDP-11 simulator on Raspberry Pi
Operating System	RSX-11M-PLUS V4.6 (BL87)
CPU Emulated	PDP-11/70
Memory	4 MB (emulated)
Storage	RP06 + RL02 disk images
Network	DECnet (HECnet), TCP/IP
Terminals	8 DZ11 lines via telnet
Front Panel	Full working switches and LED indicators

The PDP-11 was a series of 16-bit minicomputers produced by Digital Equipment Corporation (DEC) from 1970 into the late 1990s. It was one of the most successful and influential computer architectures in history.

The PDP-11 is where Unix was first ported (from the PDP-7), where the C programming language was developed by Dennis Ritchie, and where many foundational concepts of modern computing were first put into practice. BSD Unix, which influenced every modern operating system, was developed on PDP-11s at UC Berkeley.

The PDP-11/70, introduced in 1975, was the most powerful model in the original PDP-11 line. With its Unibus and Massbus architecture, cache memory, and support for up to 4MB of physical memory through 22-bit addressing, it was the workhorse of countless universities, research labs, and businesses throughout the late 1970s and 1980s.

RSX-11M-PLUS, running on this system, is DEC's real-time multi-user operating system. It supports preemptive multitasking, file-structured devices, and multi-terminal access — all running on a 16-bit computer designed half a century ago.

The PiDP-11 is a modern replica of the PDP-11/70 front panel, designed by Oscar Vermeulen. It uses a Raspberry Pi running the SimH emulator to faithfully recreate the PDP-11 experience, complete with working toggle switches and LED displays that show real system state.

The front panel is a 6:10 scale reproduction of the original PDP-11/70 panel, with functional address and data switches, and LEDs driven in real-time by the emulator. You can boot, halt, examine and deposit memory, and single-step programs — just like on the original hardware.