3 ms·
> 4.77 MHz because that is one third of the NTSC clock, 14.318 MHz. And a clock frequency related to NTSC was used here, because it allowed the use of the chea
by segfaultbuserr 6y ago
> 4.77 MHz because that is one third of the NTSC clock, 14.318 MHz.
And a clock frequency related to NTSC was used here, because it allowed the use of the cheapest quartz crystal in mass production, and also allowing systems to use same 14.318 MHz clock to drive a potential video display.