Re: A newcomer's questions ;)

Posted by cadet1620 on Nov 28, 2012; 6:09am
URL: http://nand2tetris-questions-and-answers-forum.52.s1.nabble.com/A-newcomer-s-questions-tp4025710p4025725.html

Nothing particularly magic about 33.333 MHz except that it's 1/3 of 100 MHz. In the analog world, it's easier to triple a signal's frequency that to double it, so this is a standard frequency for oscillator modules.

Another frequence that you may see a lot is 3.579545 MHz which is the "color burst" frequency for colr TV signals. Since early computers used color TV monitors for graphic output. they had to have this frequency available and higher frequency clocks were therefore multiples of it. The original IBM PC had a 4.77(2727) MHz = (4/3 * color burst freq.) clock.

--Mark