On 11/02/2017 08:18 PM, Fred Cisin via cctalk wrote: > On Sun, 29 Oct 2017, Dave Wade via cctalk wrote: >> I am not sure they invented computer emulation. I think that the concept >> Emulation/Simulation is as old as, or perhaps even older than computing. > > Henry Ford is attributed with "car racing began 5 minutes after the > second car was built." > BUT, I'm not sure whether the second computer cared about emulating > the first one. > > Emulation of another computer was important to two groups early on... designers that wanted to try new architecture and the result of evolution and retirement of hardware the need to run costly to develop programs for which source or the needed components had become extinct. The latter I believe is more rampant since the mid 70s with machines getting replaced with bigger and faster at an ever increasing rate. That cycle is wound so tight now that if you can buy it its likely obsolete. It is also part of the more computers being available and CPU cycles on them being cheaper back in the late 70s and into the 80s made it useful to use them to get the work from the last machine useful to design the next machine.
Personal example: Altair built and running by Jan 75 as an early adoptor. less than a year and a half NS* Horizon. Why? First Z80 runs 8080 code, it was faster, better hardware. It ran deeper but thats the 30,000 ft view of change. And so it went to faster, more memory till PDP-11 push that to auxiliary role followed by my first 32bit VAX. It would take 486DX/66 with networking to dislodge that. Fortunately the bigger faster could emulate the older slower sufficiently to run the software that was of greater value. So here we are... WIN10 has to have emulation/visualization to run old 32bit and earlier software as 64bit architecture gets in the way. The only reason the system is 64 bit is replacement of a dead 32bit that was satisfactory in every way save for its now unobtainium. So it goes.... I'll bet that the Henry Ford comment was followed by a comment from someone making a better car to beat the second one! It also forgets the market for used cars was born right then. Allison
