The diode board was used for the boot strap before large rims were cheap. DEC predates Intel (who got its big start with the invention of the EPROM - Only after they micro processor did they get out the memory business which we are only recently re-entering).
As for single stepping sure. The diode board is just memory. Sent from my iPhone > On Dec 16, 2015, at 6:51 PM, Will Senn <[email protected]> wrote: > > All, > I was watching an old PDP-11 video when, seriously, I came across an > explanation of programming that involved wire snips. It was interesting and > brought home to me the concept of memory pages and such. I thought I would > share the screen shot with y'all. If it doesn't come through imagine a guy > with a pair of wire cutters snipping off diodes from a ROM card for a PDP11. > Is this really how y'all programmed back in the day :)? > > <fiihgchi.> > > > Is it possible to single step through a machine language program (such as the > bootstrap loader) that was entered using deposit commands as it loads another > program (such as the absolute loader, > which this particular diode ROM represents) and similarly step through the > absolute loader itself as it loads something like DEC-BASIC from paper tape, > and if so, what does that process look like in SimH terms? > > Thanks, > > Will > <small-pliers.png> > _______________________________________________ > Simh mailing list > [email protected] > http://mailman.trailing-edge.com/mailman/listinfo/simh _______________________________________________ Simh mailing list [email protected] http://mailman.trailing-edge.com/mailman/listinfo/simh
