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For the past few nights I have been falling asleep to the extremely 70s supercomputer energy of this 12-hour Cray X-MP training video playlist, via our friend Chris:
youtube.com/playlist?list=PLOK
"Octal chauvinism" was apparently still a thing in supercomputer/minicomputer circles well into the 80s. So weird.

@phooky 18-bit and 36-bit words are *weird*. Anything that's not a power of 2 creeps me the fuck out.

@mdhughes oh, it's even better than that-- the Cray uses a 64bit word and 22bit addresses and they *still* use octal. (Technically a 72 bit word, but 8 bits are for the ECC.)

@mdhughes @phooky 12-bit PDP-8, then: it's so simple that, given octal words, you've got a fair chance of disassembling code by hand.

Downside? Integer types in PDP-8 Fortran max out at -2048…2047

@scruss @mdhughes I did use octal when writing pdp-11 machine code, because iirc the operand fields were all 3 bits long, so it was easy to do by hand. Also the boot monitor worked in octal.

@phooky
A matter of habit, I still make an effort to remember the bits corresponding to 0xb, 0xc or 0xd. With the octal system, everything is fast and automatic.
However, ``if you use hexadecimal you can do hard drives or something'' 🤣

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