Embedded Note Number Identification System

According to the new cash register standards issued by the government, cash registers should be able to recognize the number of paper currency. Recently, fake money disputes and violent robbery incidents always happen, which bring a lot of unsafe factors to people’s life and social stability. To resolve the question, this paper regard cash register as the research object, and embedded number automatic acquisition and recognition module in it,and it can count money at the same time record the serial number, so that the equipment can provide important clues to identifying fake money and robbery case detection and prevention.At present, the speed of mainstream cash registers is about20pieces per second, that means one note remain in the cash registers is50ms.In order to collect the paper currency, cutting and recognize the serial number, require the system has a high-speed, so this paper designed hardware platform based on DSP+CPLD, including note position detection unit, note image acquisition, storage unit, serial number cut, recognition unit, and data transmission and display unit. Note image acquisition and storage unit is made up of contact image sensor (CIS), analog signal processor and digital signal processor (DSP), data transmission and display unit send the recognition number to a single-chip microcomputer through the multichannel buffered serial port of the DSP. In order to make use of the DSP high-speed operation of the characteristics, CPLD completed the system logic and clock signal generation, ensure that the system has rapid acquisition and recognition.This paper completes the whole serial number of paper currency identification system design, installation and commissioning, and its running results show that the system can continuously collect a paper currency of positive and negative image information, and the time for collect one note is about47ms. The collection of paper currency image is controlled by CPLD, and the identification of serial number of paper currency is controlled by DSP, so the CPLD and DSP can work at the same time to ensure the run time. The quality of collection paper currency image dose not affected by the outside lighting condition’s change, the acquisition paper currency image can be displayed in the digital tube through the DSP multichannel buffer serial port, so the paper currency image acquisition equipment can work coordinate with the cash register which speed is1200pieces per second.