Bit twiddling method for breaking up a byte into 4 2-bit sections

two-bit-int.c

#include <stdio.h>
#include <stdint.h>

int main() {

	//set initial vars, range of 0 - 3
	int p1 = 1;
	int p2 = 2;
	int p3 = 0;
	int p4 = 3;

	//add all 4 to the 8 bit container
	uint8_t container = p1 | (p2 << 2) | (p3 << 4) | (p4 << 6);

	//retrieve them by shifting/masking
	int gp1 = container & 0x3;
	int gp2 = (container >> 2) & 0x3;
	int gp3 = (container >> 4) & 0x3;
	int gp4 = (container >> 6) & 0x3;

	//test to make sure we got the right numbers back
	printf("gp1: %d, gp2: %d, gp3: %d, gp4: %d\n", gp1, gp2, gp3, gp4);

	return 0;
}