On Wed, 2024-04-10 at 03:45 -0500, CAREY SCHUG via cctalk wrote: > you could also use the console to run 1401 emulation without DOS (i > think 2 options, one loaded in card deck, then allowed typing in > config, otherwise just turn dials and store stuff into memory.
After loading the Compatibility Initialization Deck or CID, a 1401 program could be run from cards by putting 1402 into the IPA dials, or from tape by putting 1729 into the IPA dials, and pushing IPL. The IPA was, IIRC, the address in the microcode.