Arduino-Crypto-HMAC

#include <crypto.h>

int led = 13;
//char * key = "0123456789012345678901234567890123456789012345678901234567890123"; //64 bytes
uint8_t * key = (uint8_t *) "\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0A\x0B\x0C"
                            "\x0D\x0E\x0F\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19"
                            "\x1A\x1B\x1C\x1D\x1E\x1F !\"#$%&'()*+,-./0123456789:"
                            ";<=>?";

hmac_sha1_ctx_t hctx;
uint8_t mac[20];

// the setup routine runs once when you press reset:
void setup() {

  // initialize the digital pin as an output.
  pinMode(led, OUTPUT);
  hmac_sha1_init(&hctx, key, 512);
  hmac_sha1_lastBlock(&hctx, "Sample #1", 72);
  hmac_sha1_final(mac, &hctx);
  Serial.begin(9600);
  while(!Serial);
  Serial.println("Hohohoho");

}

// the loop routine runs over and over again forever:
void loop() {
  digitalWrite(led, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(1000);               // wait for a second
  digitalWrite(led, LOW);    // turn the LED off by making the voltage LOW
  delay(1000);               // wait for a second
  for(int c=0; c<20; c++){
    Serial.print("0x");
    Serial.print(mac[c], HEX);
    Serial.print(" ");
  }
  Serial.println("");
}