Build your own Apollo Guidance Computer

Richard <legalize at xmission.com> wrote: I have hand-programmed PALs all the way from pencil-and-paper logic to putting the right volts on the right pins and hitting a one-shot to do the fuse-blowing. No computer necessary at all. It was decades ago but I did it! Non-registered PALs can also be reverse-engineered without any fancy tools (although I'll admit that I usually use a computer to do so, a couple times I have found all the possibilities for "what address does this thing decode?" with just some 7493's and a 555.) Now all that probably could be done for GALs and even FPGA's but I haven't done that :-). Even most GALS do not have publicly released programming specs. I will gladly admit that the "moral equivalent of the visible PAL" is the guy who built a processor from discrete surface mount parts where the "programmable logic" was using/not using arrays (of diodes? most likely) of parts on pluggable PCB's. Don't have the URL handy and Google isn't helping. End result seemed to be more compact and functional for homebrew processor purposes than DIP PAL's, and a lot more visible. Tim.