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 the top nibble and the bottom nibble into their own variables.

11110000 = High 4 bits throttle, to be read into $throttle, and should be a value from 0 to 15. 00001111 = Low 4 bits brake, to be read into $brake, and should be a value from 0 to 15.

Don't forget, drivers can apply the throttle and the brake at the same time, so you might get a value like 11000111. I've myself come up with a solution for the high 4 bits, and it's as simple as pushing the lower 4 bits out of the way with the >> (bit shift right) operator 4 times. $Throttle = $ThrBrk >> 4, but as I can't do that in one move for the lower four bits it looks kinda bad in my source code.