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Rebuilding the PDP-8 With a Raspberry Pi
braindrainbahrain writes: Hacker Oscarv wanted a PDP-8 mini computer. But buying a real PDP-8 was horribly expensive and out of the question. So Oscarv did the next best thing: he used a Raspberry Pi as the computing engine and interfaced it to a replica PDP-8 front panel, complete with boatloads of fully functional switches and LEDs.
We really should be preserving old computers in HDL in a form as loyal as possible to the original. Then we could always reimplement them in FPGA and make "real" hardware cheaply enough until the sun burns out.
It's doable, although these are big efforts.
There is already this Japanese guy who has done it for the SNES.
My first "personal computer" was a PDP-8i at Georgia Tech in the late 1960's. The ISy school had one in a small room in the basement with an ASR TTY (33 I think). There was another room with at least one more TTY with punch and you would code on that machine and after signing up for time on the PDP-8i you would take your paper tape in and after toggling in the boot sequence and loading the BIN tape then the Assembler you would run your tape to punch out your assembled program to run on the machine. I may be leaving out a number of steps since that was a while back.
in any case that was my first taste of writing any code in a machines assembly language and even then I dreamed of having my very own PDP-8.
This is a cool project and even for an Old Man I can fully relate to why it was done. I think this experience led to a life long career working with computers ranging from Big Iron mainframes to PC's networks and a variety of internal and Internet facing Servers. Yes, even though retired, I have a couple of Arduinos and Raspberry Pi's around to play with! Learning new things has kept me going all these years.
The SBC6120 uses a Harris 6120 CPU chip which is a PDP-8/e-like microprocessor. It has a companion FP6120 front panel with switches and lights, which is a scaled down version of an older modle rack mount PDP-8 front panel. You built them from kits, loads of fun for those who like that sort of thing. Mine has a CF card for the hard drives (a whole whopping 2 MB each under OS/8!). You may be able to find an unbuilt kit, as the maker of the kit, Spare TIme Gizmos, will not be making any new ones going forward.