A collective known as Obsolescence Guaranteed has crafted a PiDP-10, mirroring the PDP-10 mainframe computer initially released by Digital Equipment Corporation in 1966.
The initiative began in 2015. Oscar Vermeulen, a Dutch economist passionate about collecting computers, aimed to construct a single duplicate of a PDP-8 minicomputer, a device he had adored since his youth.
He told The Guardian that he owned a Commodore 64, but a friend of his father dismissed it as merely a toy. Vermeulen was informed that a genuine computer was a PDP, particularly a PDP-8. Consequently, he started searching for discarded PDP-8 computers but to no avail.
"They've become collector's pieces now, expensive and typically malfunctioning. Hence, I opted to create a replica for my use." Vermeulen realised he required a professionally crafted front panel cover.
"The manufacturing company informed me I'd have to purchase an entire four-square-meter sheet of Perspex, sufficient for 50 panels," he explained. "So, I produced 49 additional ones, assuming I'd find 49 like-minded enthusiasts. Little did I know, I'd end up crafting thousands at my dining table over the following years."
Simultaneously, Vermeulen started sharing on various vintage computing forums on Google Groups, where members were already developing software simulators for pre-microprocessor computers. As news of his replica spread, it swiftly evolved into a collaborative effort, now involving over 100 individuals.
While Vermeulen focuses on the hardware replication – the front panel with operational switches and indicators – others manage different facets of the open-source software simulation, which boasts a rich history.
At its heart lies SIMH, devised by former DEC staff member and renowned hacker Bob Supnik, which simulates a variety of classic computers. Richard Cornwell and Lars Brinkhoff subsequently enhanced it by augmenting the driver support for the PDP-10's ITS operating system and other Massachusetts Institute of Technology (MIT) initiatives.
Numerous individuals contributed along the way, preserving old backup tapes, refining and troubleshooting, or supplying documentation and diagrams.
From 1959 to the early 1970s, the PDP machines were revolutionary. They were significantly more affordable than the colossal mainframes used by the military and major corporations and were designed as versatile, interactive devices. You weren't required to create programs on punch cards, which were then processed by the IT department, who would run them on the computer and return a printout for debugging, possibly the next day.
With the PDPs, you could input directly into the computer and instantly test the outcomes.
PDPs were set up in university laboratories around the globe, where they were adopted by a new wave of engineers, scientists, and programmers – the original computer hackers.
Steve Wozniak began programming on a PDP-8, a smaller, more affordable model sold by the thousands to enthusiasts. Its operating system, OS/8, laid the groundwork for MS-DOS. Teenagers Bill Gates and Paul Allen would sneak into the University of Washington to code on PDP-10s. On PDP computers, MIT student Steve Russell and friends developed SpaceWar!, one of the earliest video games to operate on a computer.
The team circumvented many challenges through emulation. The PDP replicas all mimic the original terminal fronts with lights and switches. Yet, the computing is performed by a Raspberry Pi microcomputer connected at the back via the GPIO connector.
To activate it at home, insert the Raspberry Pi, connect a keyboard and monitor, power it up and install the software. Then, toggle a switch on the PDP-10's front, reboot the Raspberry Pi, and you're in PDP mode, with your monitor displaying a window that emulates the old Knight TV terminal screen. You can run various original programs, including games using the command-line interface (recall those?).
Chiriqui Electronic Design Studio, a firm based in Panama, is now manufacturing the hardware, and what started as a personal endeavour has grown substantially.