bit operations

bitoperations.js

console.log("Hello");

var offset = 7;

var ar = [0xfd, 0x23];

var myVal = ar[0]<<8 | ar[1];

console.log(myVal);

var read = 4;

// 1 | 1 1 0 0 0 0 0 0
// 16-7 = 9-3=6;

console.log("Shift", (16 - offset - read));
console.log("And", ((1 << read)-1));

var newVal = (myVal >> (16 - offset - read)) & ((1 << read) - 1);

console.log(newVal);