20 bit encoder test

#include <stdlib.h>
#include <stdio.h>

int checkRange(const char * varName, int x, int low, int high) {
  if (x < low || x > high) {
    printf("Out of range %s=%d, [%d-%d]\n", varName, x, low, high);
    return 1;
  }
  return 0;
}


void testPack (int a, int b, int c, int aMax, int bMax, int cMax) {
  aMax += 1;        // Increment the maximums to allow for the entire range (e.g. a max of 9 is 10 values if 0 is included).
  bMax += 1;
  cMax += 1;
  long pack = ((a * bMax) + b) * cMax + c;

  printf("Packed value: %d (0x%x)\n", pack, pack);


  long wrk = pack;
  int cUnpack = wrk % cMax;
  wrk = wrk / cMax;
  int bUnpack = wrk % bMax;
  wrk = wrk / bMax;
  int aUnpack = wrk;

  printf("Unpacked:\na=%d, b=%d, c=%d\n", aUnpack, bUnpack, cUnpack);

}


int main (int argc, char * argv[]) {
  printf("Encoder 20 bit.\n");

  if (argc != 4) {
    printf("Expected 3 numeric arguments\n");
    printf("%s a b c\n", argv[0]);
    printf(" a: [0-40]\n");
    printf(" b: [0-41]\n");
    printf(" c: [0-443]\n");
    exit(1);
  }

  int a = atoi(argv[1]);
  int b = atoi(argv[2]);
  int c = atoi(argv[3]);

  printf("a=%d, b=%d, c= %d\n", a, b, c);

  int err = checkRange("a", a, 0, 40);
  err |= checkRange("b", b, 0, 41);
  err |= checkRange("c", c, 0, 443);

  if (err) {
    exit(1);
  }

  testPack (a, b, c, 40, 41, 443);

  exit(0);
}