// Open serial port

Serial.begin(115200);

Serial.setTimeout(5000);

for (size_t i = 0; i < 8; i++)

IDstring += UniqueID[i];

// DUCO-S1 algorithm implementation for AVR boards (DUCO-S1A)

// Difficulty loop

int ducos1res = 0;

//Conversion to unsigned char *

const char * c = newblockhash.c_str();

size_t len = strlen(c);

size_t final_len = len / 2;

unsigned char* newblockhash1 = (unsigned char*)malloc((final_len + 1) * sizeof(unsigned char));

for (size_t i = 0, j = 0; j < final_len; i += 2, j++)

newblockhash1[j] = (c[i] % 32 + 9) % 25 * 16 + (c[i + 1] % 32 + 9) % 25;

//Mining loop

for (int ducos1res = 0; ducos1res < difficulty * 100 + 1; ducos1res++) {

Sha1.init();

Sha1.print(lastblockhash + ducos1res);

// Get SHA1 result

uint8_t * hash_bytes = Sha1.result();

//Compare the two in C++ code

if (memcmp(hash_bytes, newblockhash1, sizeof(hash_bytes)) == 0) {

// If expected hash is equal to the found hash, return the result

return ducos1res;

}

}

// Wait for serial data

while (Serial.available() > 0) {

// Read last block hash

lastblockhash = Serial.readStringUntil(',');

// Read expected hash

newblockhash = Serial.readStringUntil(',');

// Read difficulty

difficulty = Serial.readStringUntil(',').toInt();

newblockhash.toUpperCase();

// Start time measurement

unsigned long startTime = micros();

// Call DUCO-S1A hasher

ducos1result = ducos1a(lastblockhash, newblockhash, difficulty);

// End time measurement

unsigned long endTime = micros();

// Calculate elapsed time

unsigned long elapsedTime = endTime - startTime;

// Send result back to the program with share time

Serial.print(String(ducos1result) + "," + String(elapsedTime) + "," + String(IDstring) + "\n");

// Wait a bit

delay(25);

}