David Wilson wrote:
Michael J. Mahon wrote:I've been trying to find my copy of this manual just to verify the hack. ;-)The logic is: PROM_A6 = NAND(A6,NAND(A7,NAND(PIN_C,PIN_D))) where PIN_C and PIN_D are pins 14 & 15 on the jumper block (DIP header).
Thanks! Apparently Woz liked to think of ROMs as "logic state machines" and had no reservations about using address lines for data inputs. ;-) -michael NadaNet networking for Apple II computers! Home page: http://members.aol.com/MJMahon/ "The wastebasket is our most important design tool--and it's seriously underused."