5 ms·

Haven't followed CPU arch in a very long time so my memory may fail, but the B7700 (1977) based on B5000 (1961) architecture demonstrated what you say on an ind

by awful 10y ago

Haven't followed CPU arch in a very long time so my memory may fail, but the B7700 (1977) based on B5000 (1961) architecture demonstrated what you say on an industrial scale. The machine read in a long 48 bit string of opcodes, mapping them directly to hardware (adders, barrel shifters, inc/dec logic, branch prediction), maximizing throughput by anticipating needs for the next few clocks like setting up and (where possible) execute in different parts of the CPU. Since many operations were already present in pipeline and a cache miss or instruction branch could maybe predicted sooner you could see a long way into the future in some cases. This would leave the memory bus more free for data. And if I remember correctly, it would issue multiple (abstract?) cached stack operations to memory if possible, as the interface was quite sophisticated. And other CPUs could service the stack, SMP, if necessary. I had to troubleshoot these opcodes to the bit level back then, in 1981.

nigwil_ 10y ago
Did you keep any material about your time with the B7700? photos, printer listings, tapes, manuals? We're trying to build an emulator for the Burroughs B6700 (and by extension the B7700) so every scrap of information helps.
- i336_ 10y ago
  Very interesting! (I say this as someone interested in emulation in general, I sadly am not familiar with Burroughs equipment, although I know the name is synonymous with early cutting edge design.) Does this project have any sort of publicly accessible online home yet?
  - nigwil_ 10y ago
    nothing yet, we need to find a complete release of MCP for the Burroughs B6700 before we plan out the project.
    - i336_ 10y ago
      I see, I just took a quick look around the Googles. I'm (somewhat) nearby over the water in Sydney :P I have no idea where I'll end up in the future, but if I ever see anything interesting I now know where to send it.

by awful 10y ago

nigwil_ 10y ago

Did you keep any material about your time with the B7700? photos, printer listings, tapes, manuals? We're trying to build an emulator for the Burroughs B6700 (and by extension the B7700) so every scrap of information helps.

i336_ 10y ago
Very interesting! (I say this as someone interested in emulation in general, I sadly am not familiar with Burroughs equipment, although I know the name is synonymous with early cutting edge design.) Does this project have any sort of publicly accessible online home yet?
- nigwil_ 10y ago
  nothing yet, we need to find a complete release of MCP for the Burroughs B6700 before we plan out the project.
  - i336_ 10y ago
    I see, I just took a quick look around the Googles. I'm (somewhat) nearby over the water in Sydney :P I have no idea where I'll end up in the future, but if I ever see anything interesting I now know where to send it.