On: The Soviet 1801VM2 LSI-11 Processor (2021)

[jhallenworld]

I don't understand the reset sequence of the KM1801VM1 and VM2, but it's clear for the VM3 (it starts at 0173000 or 026 depending on WO pin).

It looks like it has status signals so that program and data memory spaces can be split, the English translation has this funny comment:

"When working with weapons of mass destruction, system memory is “hidden”, i.e. its addresses in program mode do not occupy RAM address space. "

[dmitrygr → jhallenworld]

Can you paste the original russian and i'll try to translate better? i suspect that " weapons of mass destruction" was a mistranslation of an acronym to WMD, which got then expanded

[binarin → dmitrygr]

Yeah, it should be "single-chip microprocessor" (ОМП / однокристальный микропроцессор).

[kjs3 → jhallenworld]

Many PDP-11s had "split I&D" (Instruction & Data) capability built into the MMU so you could address 128k memory instead of only 64k. See: https://gunkies.org/wiki/PDP-11_Memory_Management