I think the visual and audio effects are implemented by reusing the test programs. Just like late 80s home computers and today's microcontrollers, a basic visua

I think the visual and audio effects are implemented by reusing the test programs. Just like late 80s home computers and today's microcontrollers, a basic visual and audio demo was pretty common on large computers back to those days. But yeah, it still may have taken days or at least hours.