Issue with Caesars Cipher [SOLVED]

Hey all, I am having trouble with the Caesars cipher. It should be working and I can’t understand what the problem is. Here is the code:

function rot13(str) {
 
var ciph=[];
var decoded=[];

  
var len=str.length;

//make cipher array in character codes
for(var i=0;i<len;i++){ 

var cc=str.charCodeAt(i);

if(cc<=77 && cc>=65) { 
ciph.push(cc+13);}
  
if(cc>=78 && cc<=90) { 
ciph.push(cc-13);}

if(cc>90 || cc<65){
  ciph.push(cc);}

}
 
//join cipher array and return as string  
return String.fromCharCode(ciph.join());

}
rot13("GUR DHVPX OEBJA QBT WHZCRQ BIRE GUR YNML SBK");

If I first evaluate ciph.join() before the final return statement, and type in the string manually it works fine, but if I try to do it as above it just returns a red dot. Any ideas?

I cleaned up your code.
You need to use triple backticks to post code to the forum.
See this post for details.

That did it, thank you very much for the help.