Since machine code, ultimately, is nothing but ones and zeroes, any digital computer can, in theory, emulate any other digital computer. Whether the emulation is practical depends on, of course, the machine doing the emulating and the machine being emulated.
Reportedly, to offer a striking example of confirmation of this theory, a group of grad students some years ago wrote an 80386 emulator for the Z80. It took half an hour to get a DOS prompt, but it worked. (This may be a mere computing myth, but it illustrates the point.)
Chalk up another for The Old Node Revival Squad.