Re: PC design with DEMUX

Posted by burhan on
URL: http://nand2tetris-questions-and-answers-forum.52.s1.nabble.com/PC-design-with-DEMUX-tp4034466p4034468.html

:) , okay , it's a little mishmash.

first  , i m taking zr as input of DMux8Way.

second ,  sel = instruction[0..2] , which  are J1J2J3 as DMux8Way selection inputs.

third , there are 8 outputs of DMux8Way  ,  as jump conditions .

    "For example ; if J1J2J3 = 001 , the first outout of DMux8Way is ACTİVE.
     My first outout is zr , as named Ione.
     I mean b output of  DMux8Way = Ione.
     And im doing that ;
     
     Or   ( a = Ione , b = ng , out =orIone ) ;
     Not  ( in = orIone , out = notIone ) ;
     And  ( a = notIone , b = instruction[15] , out = outIone);
   "

Finally i use the output "outIone" as PC register "load" input.

if its one , PC ll jump
else PC ll incremant.