Hey, I found this code about this sensor... I'll put it here as aid:

//--------------------------------------------------------------------------------------------

//Fingerprint Scanner TTL demo code to show how to cmdOpen and show device id and serial number // Note: all multi byte data is little endian!

include

SoftwareSerial Scanner(11, 12); // RX as pin 11

int f; byte ResponseData[38];

void setup() { Scanner.begin(9600); Serial.begin(9600); }

void loop() { // cmdOpen with response data packet Scanner.write((byte)0x55); Scanner.write((byte)0xAA); Scanner.write((byte)0x01); Scanner.write((byte)0x00); Scanner.write((byte)0x01); Scanner.write((byte)0x00); Scanner.write((byte)0x00); Scanner.write((byte)0x00); Scanner.write((byte)0x01); Scanner.write((byte)0x00); Scanner.write((byte)0x02); // pre-calculated checksum Scanner.write((byte)0x01); delay(100);

if (Scanner.available() > 0 ) {

for (f = 0; f < 38; f++) { ResponseData[f] = Scanner.read(),HEX; } }

Serial.print("FirmwareVersion: "); for (f = 16; f < 20; f++) { Serial.print(ResponseData[f],HEX); //FirmwareVersion } Serial.println(); Serial.print("DeviceSerialNumber: "); for (f = 20; f < 36; f++) { Serial.print(ResponseData[f],HEX); //SerialNumber }

while(1){}

}

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