It was in the back shed, in a box of office stuff. With a very dead 9V battery. Methinks it'll be needing a new battery clip, but such are easily acquired.
Also in boxes of office stuff in that shed: many books I'd thought long since misplaced. Including a box of vintage CPU-architecture manuals; perhaps someday I'll make good on my threat to implement a PDP-10 in Verilog. (Implement in an FPGA, with an SDRAM chip emulating many mobies of core, and an SD card emulating a room full of washing machines... anyone got an installation CD for TOPS-10?)
And my Wile E. Coyote doll, and many other things, some of which I'll keep. Lots of stuff that gets tossed, though.
Still haven't found the foo bar, which ought to be in some office box or other. Probably in a Ciena box, in the side shed. When did I last see it?
Let's see... RP06 washing machine holds 178MB, formatted. So, 5.6 washing machines to the gigabyte; a 16GB flash card holds about 90 washing machines of data. Peak transfer rate on the RP06 is 36 bits per 5.6μs, or 6.43 Mbits/sec; a Class 10 SDHC card has a sustained write speed of at least 80 Mbits/sec, which isn't usefully comparable, really, but I suspect that in practice a moderately capable SD card would actually outperform a fair-sized array of vintage spinning-rust units. How many disk drives was it possible to connect to a single PDP-10, anyway?
Update: Hello! ITS source code is on Github! So if some fool goes and builds a PDP-10 datacenter-on-an-index-card, the software for it is out there. Might take a kinda high density connector to bring all the terminal ports off the board, if 'tis to be used for timesharing.
Update 2: Hmmm. Initial thought is that I want an FPGA in a QFP, because BGAs are such a pain. I did once design a board (painfully) with a 1mm pitch, 256-ball package (a Spartan 3E, in fact), using 6 layers, 5 mil trace & space, and 10 mil (0.25mm) minimum drill. If memory serves, that was an expensive board to get fabbed (but the client handled that part of the project).
Decently capable FPGAs are still largely BGA things, alas, but possibly-suitable Spartan 6 parts are at least available in 1mm pitch packages, not just the fine- and superfine-pitch ones.
And... getting prototype boards done has gotten cheaper! Seeeeeeeed quotes $433.89 for 10 pieces of a 100mm square board with 6 layers, 4 mil trace & space, and 0.2mm (8 mil) minimum drill. Vastly more expensive than a 4-layer board, but not absurdly out of reach, and the unit price isn't too bad, in case there turned out to be a market for such a dingus.
But it's still a stupid idea. Not that that's ever stopped me before.
Update 3: Just for giggles, I also checked JLCPCB's pricing for a prototype board run (10 pieces) with approximately the above specs. Ninety. Six. Bucks. Wut? That's getting into "what the heck, make the thing just because" territory. But I don't have time right now, I'm not up to speed on DipTrace yet (and such a complex board seems excessive as a learning project), and by the time I get around to it prices will likely be even lower. Ah: I see JLCPCB has broken out pricing for >10 runs, with (for my 6-layer example) a $159 or something setup charge plus a pittance per piece. For 10-piece orders, it's the special prototype pricing without a setup charge as such.
(Probably can't get away with using these cut-rate furrin suppliers for ITAR stuff, especially for mil-spec deliverables, but for most of my own projects, no problem.)
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