Actual application code was hardwired, entered manually with switches and lights, or with punch cards. Later, when ICs were sufficiently advanced, mask-programmed ROMs/PLAs.
Actual application code was hardwired, entered manually with switches and lights, or with punch cards. Later, when ICs were sufficiently advanced, mask-programmed ROMs/PLAs.
Or diode matrix ROMs were pretty popular as well.
Electrically, essentially what happens in most mask ROMs, but as a circuit board that allowed you to solder in a diode or not in each bit location in order to specify a 1 or a 0.
That would be the "hardwired" option.
Eh, it was considered user programmable and generally came blank from the vendor.