The basic concept in fingerprint system

       The fingerprint features

       The fingerprint algorithm extracts features from fingerprint image. The store, match and search of fingerprint is operated by means of fingerprint features.

       1: 1 match

  Two fingerprint features are compares with each other. The return message is either match or no.

        1:N search

  From N fingerprints, get one fingerprint out of N fingerprints to compare with 1 given fingerprint feature. The return message is: no match or match and returning match feature number.

 Live finger validation

  In SM-628B fingerprint module, the function of live finger validation is designed on order to prevent fake fingerprints. The live fingerprint validation has two phase as 0 and 1. 0 is off; 1 is on. However, this function is sensitive to environment temperature, humidity and wetness of the finger.

In order to increase the robust of the system, and to prevent the un-sensitivity with fingerprint detection, it is recommended to search fingerprints one more without the live fingerprint validation in the same time. 

Technical parameters

* 1bit start bit, 8 bits data bit, 1bit stop bit Baud rate 57600bps