Reading top nibble and bottom nibble in a byte

Question

What\'s the correct way to handle two distinct values being stored in one byte of data. I have a byte that contains two nibbles each containing their own data. I want to read th

Answer 1

Use ANDoperators for both and shift the top nibble four bits to the right.

$brake = $value & 0x0F;
$throttle = ($value & 0xF0) >> 4;

Answer 2

Check out the & operator, which is a bitwise AND. To get the first (least significant bit), do this:

$lsb = $bits & 1;

So, to get the whole "nibble":

$break = $bits & 15;