Contemporary embedded systems are habitually based on microcontroller’s i.e. CPUs in the company of integrated memory as well as peripheral interfaces but ordinary microprocessors by means of external chips for memory and peripheral interface circuits are also still common, especially in more complex systems. Radio frequency identification (RFID) technology may not only be useful for streamlining inventory and supply chains: it could also make shoppers swarm. ZigBee is based on an IEEE 802.15 standard. ZigBee devices often transmit data over longer distances by passing data through intermediate devices to reach more distant ones, creating a mesh network; i.e., a network with no centralized control or high-power transmitter/receiver able to reach all of the networked devices. This paper provides centralized and automated billing system using RFID and ZigBee communication. Each product of shopping mall, super markets will be provided with a RFID tag, to identify its type. Each shopping cart is designed or implemented with a Product Identification Device (PID) that contains microcontroller, LCD, an RFID reader, EEPROM, and ZigBee module. Purchasing product information will be read through a RFID reader on shopping cart, mean while product information will be stored into EEPROM attached to it and EEPROM data will be send to Central Billing System through ZigBee module. Code Shoppy The central billing system gets the cart information and EEPROM data, it access the product database and calculates the total amount of purchasing for that particular cart. Main aim of this paper was to provide an automatic billing to avoid queue in malls and super markets.
he fig shows the concept of Central Automated Billing System. Since each cart is attached with product identification device (PID), through ZigBee communication PID sends its information to central automated billing system, there it calculates net price for the purchased products. Customer can get their billing information at the packing section according to their Cart Identification Number. Even there’s is no need for a cash collector, in case customer uses their debit/credit for bill payment. The Automated central billing system consists of a ZigBee transceiver and a server/system connected to access product database. The automated billing system will be developed using visual basic. Visual Basic was designed to accommodate beginner programmers. Programmers can not only create simple GUI applications, but to also develop complex applications. Programming in VB is a combination of visually arranging components or controls on a form, specifying attributes and actions for those components, and writing additional lines of code for more functionality. Since VB defines default attributes and actions for the components, a programmer can develop a simple program without writing much code. Programs built with earlier versions suffered performance problems, but faster computers and native code compilation has made this less of an issue.
The data transfer between microcontroller and EEPROM is made through I2C serial protocol. Since AT24C02 is two line serial I2C enabled IC. Generation of clock signals on the I2C-bus is always the responsibility of master devices; each master generates its own clock signals when transferring data on the bus. Bus clock signals from a master can only be altered when they are stretched by a slow-slave device holding-down the clock line, or by another master when arbitration occurs. Due to the variety of different technology devices (CMOS, NMOS, bipolar) which can be connected to the I2C-bus, the levels of the logical ‘0’ (LOW) and ‘1’ (HIGH) are not fixed and depend on the associated level of VDD. One clock pulse is generated
This application creates an automated central bill system for supermarkets and mall. Using PID, customers no need to wait near cash counters for their bill payment. Since their purchased product information is transferred to central billing system. Customers can pay their bill through credit/debit cards. The 8- microcontroller used here has the capability of receiving 8-bit data from RFID reader. The AT89S52 doesn’t have inbuilt I2C protocol, programmer has to create a separate EMBEDDED C program to communicate with EEPROM. This may create some difficulties in writing program for programmers to synchronize with EEPROM. Some of other microcontrollers and microprocessors have inbuilt I2C protocol features. Those can be used as further improvement in efficiency and compatibility of this application.