The present invention relates to a system which allows third-party smart cards to be recognized by computing devices configured to receive smart cards. The first and second jaw handles each have a handle portion and a clamping portion. The gate of the PFET is connected to the output of the memory cell and the source of the PFET is connected to the control signal of the memory cell. As a result, by only recording a desired finishing code in the IC, it is possible to obtain a photographic print corresponding to the desired finishing code instead of to the a finishing code recorded on the bar code during production. Applications that generate data for transmission may register those portions with the service for checksum calculation. By virtue of the disclosure, the detection of a difference frequency signal can be eliminated, thereby reducing the complexity and cost of a periphery control circuit while ensuring the control accuracy, effectively improving the stability and reliability of the control process, and improving the modulation and transmission performance of optical signals in the whole system.