Read-write system design of RF card based on MF-RC500 and MSP430f1232
source: China card network Author: Liu Jiancheng, Zou Yongzhuo, Zeng Guangxin, Feng Wei time: 2012-04-18
MF-RC500 complete all types of passive non-contact communication mode and protocol, is an integrated radio frequency chip advanced, this paper designs a MF-RC500 based on the radio frequency card read-write system, system main controller with ultra low power characteristics of MSP430 series microcontroller. Based on the system block diagram of system hardware circuit design, the design of MSP430F1232
Interface with the MF-RC500 and the antenna and the EMC circuit design; in addition the system initialization program and RF card processing program. The system can read and write Mifare Pro, Mifare One, Mifare Light RF card, has the certain versatility.
MF-RC500 is the integrated radio frequency chip developed by Philips to support the ISO14443A of all the layers, the RF communication integrated reader used in 13.56MHz carrier frequency, chip using the modulation and demodulation technology advanced, complete integration of the 13.56MHz under all types of passive contactless communication modes and protocols. MSP430F1232
Ultra low power consumption is developed by TI microcontroller, the MSP430 series microcontrollers, each module of the system is completely independent operation, independent operation timer, A/ D converter, a watchdog, liquid crystal display, can sleep in the main CPU state, when the need to master CPU work when any one module can be interrupt CPU, which makes the system run with the lowest power consumption, this is the biggest difference between MSP430 series microcontroller is the most prominent advantages but also with other single. This paper uses the ultra low power microcontroller MSP430F1232
Combined with the MF-RC500 design of a low power RF card reader system, RF card reader system consists of a microcontroller, RF chip, antenna, data memory, liquid crystal display and RS485 communication module. The figure 1 is expressed as:
micro controller MSP430F1232
To control the RF chip MF-RC500 driver antenna to close Mifare One read and write operations return data from the controller, after writing the data in the data memory or directly transmitted to the PC machine and drives the LCD display relevant information, up to a certain amount of data and then through the RS485 to transfer data to PC machine, used for storage, analysis. Data storage system was developed using Microchip's 32 Kb SPI serial EEPROM chip 25AA320A, the chip has fast byte and page level write function, the data access time at speeds up to 10 MHz, and maintain the 1000000 erase / write high durability and leading industry 200 years to save time, convenient SPI port is directly connected with the microcontroller. LCD controller with Chinese font ST7920, serial mode is connected with the micro controller used in the system.
1 circuit system design of
hardware consists of microcontroller and RF chip interface, RF chip and antenna interface, microcontroller and data memory interface, MCU and LCD display interface and a RS485 interface, this paper introduces microcontroller and RF chip interface and RF chip and antenna interface. Figure 2 and figure 3 are microcontroller and RF chip interface circuit and RF chip and antenna interface principle diagram.
in Figure 2, the MF-RC500 D0-D7 for bidirectional data bus pins, address multiplexing, IRQ interrupt request signal pin, NCS chip select disable signal pin, NWR to write disable signal pin, NRD for reading prohibited signal pin, ALE address latch enable signal pin, RSTPD as the reset signal pin MF-RC500 above all, the pins are with Schmidt trigger.