Reproducing old machines with newer technology (Re: PDP-12 at the RICM)

I'm missing something in this discussion, I think. HDL's (take your pick) are just programming languages like FORTRAN or C with different constraints. What's the point of going to all the trouble of doing an FPGA implementation of a slow old architecture, when pretty much the same result could be obtained by running a software emulator? Neither accurately reflects the details of the real thing--and there will always be the aspect of missing peripherals. Perhaps the worst aspect of using FPGA is that this is a rapidly moving field, so that the part you used to do your implementation 10 years ago will no longer be available. I've done a few designs using 5V CPLDs (XC95xx series) not *that* long ago. Now they themselves are quaint examples of obsolete hardware. You can't win. You can move software-only simulators quite easily, but I'm not as sanguine about FPGA designs. And you still don't have the peripherals. I suppose one could emulate a Univac Solid State machine in FPGA, but what would one do about the all-important drum coupled to the card reader and printer. Has anyone rolled out a design for a DIY 1403 printer? I've run the Cyber emulator as well as various SIMH emulators from time to time, but it's just not the same as the real thing--it's not even remotely the same. --Chuck