Homebrew Cray-1

egil writes "Chris Fenton built his own fully functional 1/10 scale Cray-1 supercomputer. True to the original, it includes the couch-seat, but is also binary compatible with the original. Instead of the power-hungry ECL technology, however, the scale model is built around a Xilinx Spartan-3E 1600 development board. All software is available if you want to build one for your own living room. The largest obstacle in the project is to find original software."

Comments

Re:Wow!

[Space cowboy]

S3E's have DCMs (Digital Clock Managers) making them very flexible in terms of what the internal clock frequencies are, even with a fixed input frequency.

Chances are (I can't get to the site) it just runs at 33MHz as its best-supported clock frequency. An S3E is a pretty cheap and slow FPGA - I remember writing a 32-bit CPU for one, and until I started optimising the logic-placement in the FPGA, it was only running at ~30MHz. I got it up to ~50MHz after tweaking and pipelining, but his design may do more than my simple CPU.

Simon

Re:The originals really are something else

[drfuchs]

"Why," you may ask, "was the internal wiring so insanely packed?" The length of each point-to-point wire was individually calibrated, such that all the signals to each gate arrived at the same moment, so you didn't need flip-flops to latch values in the flow of the circuits. Kind of a "just-in-time delivery" of electrons; and each layer of buffering avoided saved you delay along the pipeline. I don't think this sort of scheme was used on any other mainframe.

NCAR

[Fishbulb]

Send an email to the folks at the CISL division of NCAR.

They know a thing or two about Crays.

Chris - see the Supercomputer Centers, CMU, UCSD

[garyebickford]

I think there were (are?) four of Supercomputer Centers that had Cray 1 and later Cray X-MP machines. The Pittsburgh center did a lot of work with Carnegie Mellon, esp. the Robotics Institute.

I personally did one bit of work - porting a photometrically correct ray-tracer by Dr. Robert Thibadeau in the Image Understanding Laboratory from an Apollo workstation to the Cray at PSC - this would have been in 1989, I think. The one complication we had was that the Cray floating point format was different, so our first runs were all zeros. Other than that the code compiled and ran fine on the Cray. Of course, a run that took two weeks on the Apollo ran in about 40 seconds on the Cray.

A lot, maybe all of the work done on these machines was non-spooky research so perhaps you can track some of the professors at the associated universities, such as CMU, Northern Illininois, UCSD, Berkeley, etc. Also check out the weather folks - they have been among the biggest CPU cycle-burners for a long time. I worked briefly with one weather guy at a weather research facility in Wyoming but I don't recall any details - was it U Wy?
The SCs I recall are:

• SDSC (San Diego Supercomputer Center),
• PSC (Pittsburgh Supercomputer Center).
• NCSA (National Center for Supercomputing Applications)

I'm sure that if you dig around in the universities you'll find folks who have stuff piled on a back shelf somewhere (probably in a tape format you can't read). Also look up in the old annals of the ACM SIG on supercomputing - that will give a line on researchers who were working on the Cray.