Thingiverse
PDP2011 Support Bracket by stevenfalco
by Thingiverse
Last crawled date: 4 years, 5 months ago
The PDP-11/70 is an iconic minicomputer from the 1970's, beloved by many as one of the early homes for the Unix operating system, as well as many operating systems from Digital Equipment Corporation, the computer's manufacturer.
While it is pretty difficult to run (or even find) a real PDP-11/70 today, fortunately, there is a replica called a "PiDP-11", as described here: https://obsolescence.wixsite.com/obsolescence/pidp-11
While the replica can use a Raspberry Pi to emulate the 11/70 CPU and its peripherals, it can also use an FPGA implementation, as described here: https://pdp2011.sytse.net/wordpress/pdp-11/
The FPGA implementation of the PDP-11 typically uses an Ethernet adapter and a micro SD card interface from Digilent. Those components, known as "PMODs" don't physically fit very well into the PiDP-11 chassis, so I designed a housing for them that bolts onto the back of the PiDP-11 chassis.
The housing has guide slots for the PCBs of the PMODs, as shown in one of the photos I uploaded.
You might have to adjust the dimensions slightly, depending on whether the PMODs are too loose or too tight in your housing, so I've included both the FreeCad design file, and the STL. For my build, the Ethernet adapter was very tight, so I didn't have to add anything to retain it; it was basically a press fit.
The uSD interface was a bit loose, so I drilled a small hole and inserted a 2 mm machine screw to retain the module in place, as shown in one of the photos. One could also use hot-melt glue to retain the modules, if preferred, or even modify the design to include a retaining clip of some sort.
I printed this object with the openings for the PMODs down against the build plate. You will need supports for the two flanges on the sides (the ones with the mounting holes). Tree supports in Cura worked well for that.
While it is pretty difficult to run (or even find) a real PDP-11/70 today, fortunately, there is a replica called a "PiDP-11", as described here: https://obsolescence.wixsite.com/obsolescence/pidp-11
While the replica can use a Raspberry Pi to emulate the 11/70 CPU and its peripherals, it can also use an FPGA implementation, as described here: https://pdp2011.sytse.net/wordpress/pdp-11/
The FPGA implementation of the PDP-11 typically uses an Ethernet adapter and a micro SD card interface from Digilent. Those components, known as "PMODs" don't physically fit very well into the PiDP-11 chassis, so I designed a housing for them that bolts onto the back of the PiDP-11 chassis.
The housing has guide slots for the PCBs of the PMODs, as shown in one of the photos I uploaded.
You might have to adjust the dimensions slightly, depending on whether the PMODs are too loose or too tight in your housing, so I've included both the FreeCad design file, and the STL. For my build, the Ethernet adapter was very tight, so I didn't have to add anything to retain it; it was basically a press fit.
The uSD interface was a bit loose, so I drilled a small hole and inserted a 2 mm machine screw to retain the module in place, as shown in one of the photos. One could also use hot-melt glue to retain the modules, if preferred, or even modify the design to include a retaining clip of some sort.
I printed this object with the openings for the PMODs down against the build plate. You will need supports for the two flanges on the sides (the ones with the mounting holes). Tree supports in Cura worked well for that.