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Re:Building the PiDP-11 Dec PDP-11 Replica Minicomputer by watsocd on Wednesday November 23, 2022 @03:11PM (#33723948)
The best I could find was a Dhrystone Benchmark of about 800MIPS for the PDP11/70.

The Raspberry PI3 is rated 2,411MIPS.

This emulator must be much faster than the original PDP11 even with the emulation software.

Re:Building the PiDP-11 Dec PDP-11 Replica Minicomputer by zh3 on Wednesday November 23, 2022 @03:23PM (#33724064)
800MIPS? Not off an 11/70, for sure - much, much slower than that. 11/23's were as fast (or faster, depending on options and application) and they were maybe a single MIP or so (still got a couple of PDP11's kicking about, every so often I fire them up just to check my hearing).
Re:Building the PiDP-11 Dec PDP-11 Replica Minicomputer by bdavis__ on Wednesday November 23, 2022 @03:27PM (#33724102)
From memory.

(The original) VAX 11/780 was a 1 MIPS machine. 32 Bit.

pdp 11 was a slower machine. plus it was 16 bit. slow clock, a relatively cheap o'scope could be used to snoop the buses.

Re:Building the PiDP-11 Dec PDP-11 Replica Minicomputer by timonoko on Wednesday November 23, 2022 @03:41PM (#33724256)
50 cent EPS-8266 would make excellent PDP-11. Except much too much memory. And 20 times too fast.
Re:Building the PiDP-11 Dec PDP-11 Replica Minicomputer by dekhn on Thursday November 24, 2022 @10:22AM (#33732306)
Re:Building the PiDP-11 Dec PDP-11 Replica Minicomputer by zh3 on Wednesday November 23, 2022 @03:35PM (#33724189)
Indeed, back in the day we bolted QBus backplanes to the side of DIN41612 backplanes and wire-wrapped across to a bunch of boards each with 100+ TTL chips on them (the 5V PSUs were something like 120A). The bus clocked at around a MHz, hence loosely the instruction rate (and back then, the addressed memory or peripheral needed to ack the bus cycle or there'd be a bus fault).
Re:Building the PiDP-11 Dec PDP-11 Replica Minicomputer by williamDafoe on Wednesday November 23, 2022 @05:04PM (#33725108)
The original PDP-11/70 was 0.7 vax mips. So it was 70% as fast as a Vax 11/780. I believe (from memory) the Vax 11/780 could do ~1757 dhrystone 2.1 mips so a PDP-11/70 would be about 1230 dhrystone mips. https://wiki.cdot.senecacollege.ca/wiki/Dhrystone_howto
Re:Building the PiDP-11 Dec PDP-11 Replica Minicomputer by j_not_j on Wednesday November 23, 2022 @08:05PM (#33726641)
..."just to check my hearing"

I got a good laugh out of that....

Re:Building the PiDP-11 Dec PDP-11 Replica Minicomputer by watsocd on Thursday November 24, 2022 @02:15AM (#33728575)
Yes. Looks like I slipped a few decimal points.