CN202331517U - Multi-microcontroller radio frequency identification reading and writing device - Google Patents

Abstract

The utility model belongs to the radio frequency identification technology, in particular to a multi-microcontroller radio frequency identification read-write device. The utility model includes a radio frequency transceiver unit group, a micro-controller control unit group, a main micro-controller control unit, a stabilized power supply unit, a storage unit, a display unit, a reset unit, a program programming unit, an upper computer interface, a micro The controller control unit group includes at least two microcontroller control units, and the radio frequency transceiver unit group includes at least two radio frequency transceiver units, wherein the microcontroller control unit controls the corresponding radio frequency transceiver unit, and the radio frequency transceiver unit has different configurable radio frequencies aisle. The utility model greatly improves the reading efficiency of the reading and writing device, and solves the problem of a large amount of data redundancy in the reading and writing system.

Description

A multi-microcontroller radio frequency identification read-write device

technical field

The utility model belongs to radio frequency identification (RFID, Radio Frequency IDentification) technology, in particular to a multi-microcontroller radio frequency identification reading and writing device including RFID reader technology.

Background technique

RFID technology is a non-contact automatic identification technology. It uses radio frequency electronic equipment to emit radio frequency signals, and through the spatial coupling of radio frequency signals to automatically identify target objects and obtain relevant data, and at the same time, new information can be written into the target object. Identify the device. The RFID system is mainly composed of readers, electronic tags, external terminals, etc., and is generally divided into active systems and passive systems. For example, in an active system, the main function of the reader is to receive the radio frequency signal transmitted by the electronic tag through the antenna, perform filtering, demodulation, amplification, decoding and decoding processing, and realize the fixed data stored in the tag and the tag data area. Data reading, and sending relevant control commands or data information through the external terminal, to complete the various function control of the tag and the modification of related data.

With the continuous expansion of the application field, many applications require the read-write device to be able to process a large number of tags at the same time, while the single-frequency RFID system is simple in structure and easy to implement, but its defects are fatal, such as in the active RFID "roll call" In the system, most systems can only read about 100 tags per second, which is not suitable for applications with dense tags. In addition, system commands and data are concentrated on one channel, which is easy to be captured, analyzed, and cracked. Once the designated channel is blocked or interfered, the entire system will be inefficient or even paralyzed.

The RFID system of multi-channel transmission disperses a large number of RFID tags to different channels, that is, different tags have certain frequency differences within the main transmission frequency bandwidth, and different read-write devices have one or several frequency channels corresponding to them. In a multi-tag multi-reader system, the multi-channel transmission RFID system can avoid the "collision" problem in the system to a certain extent, and has higher read and write performance than a single-frequency system. The existing multi-frequency channel reading and writing device uses a microcontroller to directly read the data of multiple RF modules with different frequencies. The "collision" on a single channel still exists, and certain repetitions will inevitably be read in the same RF module. The data may fail to read other module data in time, that is to say, the data of a certain module read by the processor must contain repeated labels, and when the processor finishes reading the RF module, the next module When reading data, it is difficult to ensure that the data packets in the next radio frequency module and the data packets read by the module are not repeated, which greatly restricts the "reading efficiency" of the read-write device.

In addition, after more in-depth analysis and practice, the number of frequency channels included in this type of read-write device in practical applications is limited by the performance of the main controller and the number of related communication interfaces. At the same time, a large number of repeated tag data information read by the read-write device, that is, the problem of "data redundancy", has caused a serious waste of system resources, and even if data filtering mechanisms such as "conditional query" are used at the microprocessor level, it will also This creates a certain amount of processing pressure on the microprocessor side.

The "reading efficiency" of the system is an extremely important performance index, that is, the number of different tags read within a specified time or the reading time under a certain number of tags. According to the working principle of the RFID system, when the length of the tag data packet is determined, the "reading efficiency" of the system has an upper limit, that is, all the tags of the reader have no "collision" within a certain reading time. Possibly use appropriate communication strategies to guarantee this condition. In fact, the "collision" phenomenon is unavoidable, but in a multi-channel transmission system, the use of appropriate communication strategies can be equivalent to no "collision" in the reading process of several tags.

Contents of the invention

The purpose of the utility model is to provide a multi-micro-controller radio frequency identification read-write device that improves reading efficiency and avoids data redundancy.

The purpose of this utility model is achieved in that:

The multi-microcontroller radio frequency identification reading and writing device includes a radio frequency transceiver unit group, a microcontroller control unit group, a main microcontroller control unit, a stabilized power supply unit, a storage unit, a display unit, a reset unit, a program burner Write unit, host computer interface, wherein the radio frequency transceiver unit in the radio frequency transceiver unit group is correspondingly connected to the microcontroller control unit in the microcontroller control unit group, the microcontroller control unit group is connected to the main microcontroller control unit, the storage unit, The display unit and the host computer interface are respectively connected to the main microcontroller control unit, and the reset unit, the program programming unit, and the stabilized power supply unit are connected to the main microcontroller control unit and the microcontroller control unit group at the same time. It is characterized in that the microcontroller The control unit group includes at least two microcontroller control units, and the radio frequency transceiver unit group includes at least two radio frequency transmitting units, wherein the microcontroller control unit controls the corresponding radio frequency transceiver unit, and the radio frequency transceiver unit has different configurable radio frequency channels .

The main microcontroller control unit and the microcontroller control unit group are connected through a serial interface bus and a general input/output pin (GPIO). The main microcontroller control unit works in the active mode of serial interface data transmission, and the microcontroller The control unit works in passive mode for data transmission on the serial interface.

The microcontroller control unit has different serial interface data transmission priorities, and the state of the priority is controlled by the main microcontroller control unit.

The beneficial effect of the utility model is: compared with other similar read-write devices, through the essential improvement of the structure of the read-write device, the reading efficiency of the read-write device is greatly improved, and the problem of "collision" of tags is effectively solved, that is, each The data transmission between the radio frequency transceiver unit and the corresponding microcontroller control unit is completed independently. When the main controller control unit reads the radio frequency data in a certain microcontroller control unit, the unread microcontroller control unit is the pre-set of the data. The read is well prepared to achieve "non-collision" equivalence; it is worth mentioning that even if the main controller control unit side adopts the direct upload mode, the processing of the previous stage distributes redundant data to multiple modules Independent filtering also greatly reduces the data processing pressure on the controller side of the read-write system, so the utility model well solves a large number of "data redundancy" problems in the read-write system.

Description of drawings

Fig. 1 is the structural schematic diagram of multi-microcontroller radio frequency identification reading and writing device;

Fig. 2 is a schematic diagram of embodiment 1;

Fig. 3 is the schematic diagram of embodiment 2;

Fig. 4 is a schematic diagram of embodiment 3.

Detailed ways

Below in conjunction with accompanying drawing and specific example the utility model is described further.

As shown in Figure 1, a multi-microcontroller radio frequency identification reading and writing device includes a radio frequency transceiver unit group 101, a microcontroller control unit group 102, a main microcontroller control unit 103, a stabilized power supply unit 104, Storage unit 105 , display unit 106 , reset unit 107 , program writing unit 108 , host computer interface 109 , and other peripheral units 110 . Wherein the radio frequency transceiver unit 101n in the radio frequency transceiver unit group is correspondingly connected to the microcontroller control unit 102n in the microcontroller control unit group, and the microcontroller control unit group is connected to the main microcontroller control unit, storage unit, display unit, host computer The interface and other peripheral units are respectively connected to the main micro-controller control unit, and the reset unit, the program programming unit and the stabilized power supply unit are simultaneously connected to the main micro-controller control unit and the micro-controller control unit group.

The radio frequency transceiver unit group 101 includes at least two radio frequency transceiver units. According to the main working frequency band of the multi-microcontroller radio frequency identification reading and writing device, radio frequency transceiver chips such as the radio frequency transceiver chip nRF24L01+ that support frequency configuration can be selected in this group, and the microcontroller The control unit group 102 includes at least two microcontroller control units. The performance requirements of the microcontroller control unit in the microcontroller control unit group are not high, and can be selected as low-end microprocessor series chips such as C8051F320. In addition, the radio frequency transceiver unit group and the microcontroller control unit group can be combined in the actual implementation process, that is, the radio frequency chip nRF24LE1 integrated with the microcontroller can also be selected. The radio frequency transceiver unit and its microcontroller can independently complete the reading, filtering and storage of radio frequency tag signals.

In the main micro-controller control unit 103, in order to ensure the read-write performance of the device, a series of high-end microprocessors can be selected, such as LPC2388 ARM chips and the like. The main microprocessor control unit is connected with the microcontroller control unit group controlling the radio frequency transceiver unit through the serial interface bus and GPIO pins, wherein the main microcontroller control unit works in the active mode of serial interface data transmission, and the microcontroller The microcontroller control unit in the microcontroller control unit group works in the passive mode of serial interface data transmission. The serial interface can be selected as SPI (Serial Peripheral Interface), SSP (Synchronous Serial Port) and so on.

The microcontroller control units in the microcontroller control unit group have different serial interface data transmission priorities during data transmission, and the status of the priority is controlled by the main microcontroller control unit in real time, and the main microcontroller controls The unit can store, filter and process the data of several microcontroller control units, display in real time or upload data through the host computer interface. Among them, the upper computer interface can be selected as a general asynchronous receiving/sending interface, a universal serial bus interface, an Ethernet interface, and the like.

The stabilized power supply unit is used to connect with each unit and subunit of the read-write device to provide it with one or more stable working voltages.

According to FIG. 1 , the device will be described in more detail below in conjunction with embodiments.

Example 1

As shown in Figure 2, the radio frequency transceiver unit group 201 selects the radio frequency transceiver chip nRF24L01+ whose central working frequency band is 2.45GHz, the microcontroller control unit group selects the C8051F320 micro-control chip, and the main microcontroller control unit 203 selects the LPC2388ARM microcontroller chip, The main microprocessor LPC2388 and several C8051F320 controlling the radio frequency transceiver unit carry out data transmission through the SPI bus and connect the necessary control pins. The host computer interface 209 selects a standard RS232 serial port, and the regulated power supply module 204 provides stable power for the entire circuit. 5V and 3V power supplies.

Example 2

As shown in Figure 3, the radio frequency transceiver unit group and the microcontroller control unit group are integrated and merged into a radio frequency transceiver unit group 301 embedded in a microcontroller. The microcontroller control unit 302 selects the LPC2388 ARM microcontroller chip, the main microprocessor LPC2388 and several nRF24LE1 chips with microcontroller control functions perform data transmission through the SPI bus, and connect the necessary control pins, the host computer interface 308 A standard RS232 serial port is selected, and the regulated power supply module 303 provides stable 5V and 3V power supplies for the entire circuit.

Example 3

As shown in Fig. 4, the data transmission method of the utility model is described by taking Embodiment 2 as an example. nRF24LE1.k represents the kth radio frequency transceiver unit in the radio frequency transceiver unit group embedded in the microcontroller, REQ.k represents the data transmission request identification of the radio frequency transceiver unit, CS.k represents the SPI bus chip select of the radio frequency transceiver unit, PRI.k represents the data transmission priority identifier of the radio frequency transceiver unit.

Relevant microcontrollers are initialized first, in which the data transmission request identification and data transmission priority are both 0, and the SPI bus chip selection is 1 (invalid). When the microcontroller that controls the radio frequency transceiver unit receives valid data, if it is judged to be repeated tag data, it will receive the next data packet after returning, and if it is judged to be non-repetitive tag data, the data will be written into the cache and judged Whether the data transmission request flag is 1, if not, set it to 1, then judge whether there is a valid chip selection signal, if not, then receive the next data packet, repeat the process, if there is a valid chip selection signal, then Start the passive mode of SPI data transmission, clear the cache until the transmission is completed, and set the data transmission request flag to 0. If it is judged that valid control command data is received during the SPI data transmission process, the corresponding interrupt processing will be performed.

After the main micro-controller control unit receives the effective data transmission request identification, the data transmission priority of the corresponding micro-controller control unit is set according to the identification, and a valid chip selection signal is provided for the micro-controller control unit with the highest priority and Start the active mode of SPI data transmission; after the data transmission is completed, the main microcontroller control unit decides whether to upload data or perform other operations according to the content of the SPI transmission data. When uploading data, it needs to perform direct upload or conditional upload according to the upload mode. If it is conditional upload Mode, perform conditional query, modify the corresponding cache table after uploading (the tag data content in the SPI data includes a variety of information, the information content may be to upload the data, or request the reader to send a command to the tag etc. wherein the upload mode is predetermined.); after the main microcontroller control unit uploads the data, set the corresponding chip select signal to 1, and readjust the data transmission priority of the microcontroller control unit group, and then return to repeat the process process; if a host computer command is received during this process, then judge the command number, set the corresponding chip select to 0, start the active mode of SPI data transmission, and send command data; when adjusting the priority of data transmission, the transmitted data with The priority of the microcontroller control unit with the highest priority is set to zero, and the priority of other non-zero priority units is increased by one priority; when the data request identification judgment is repeated, if there are at least two new valid data transmission request identifications at the same time , when setting the data transmission priority, the priority order is set according to the microcontroller control unit number, and its priority level is set after the existing non-zero priority. The request transmission identification can distinguish different microcontroller control units. There is a data transmission priority dynamic table in the main microcontroller, corresponding to the number of microcontrollers in the microcontroller control unit. It is worth noting that there is no data transmission request The identified MCU has no data transmission priority, that is, 0 is always the lowest. When the transmission with the first MCU that sends the request identifier (its priority must be the highest) is over, it must not have a data request identifier, then its priority value is changed to 0, and it is ranked last, and other non-zero The priority is increased by one level. Then the second priority becomes the highest at this time, and the 0 priority remains unchanged. For the MCU corresponding to the 0 priority, there may be more than two MCUs when the data request identifier is judged next time, so they are arranged after the non-zero priority according to the number.

The above-mentioned implementation examples are to help readers understand the principles of the utility model, and should be understood as the protection scope of the utility model, and are not limited to such special statements and implementation examples. All possible equivalent replacements or changes based on the above descriptions are considered to belong to the protection scope of the utility model.

Claims (3)

1. multi-microcontroller radio frequency identification read-write device; Comprise a Transmit Receive Unit group, microprocessor controls unit group, host microcontroller control module, power supply unit of voltage regulation, storage unit, display unit, reset unit, program burn writing unit, host computer interface; Wherein the correspondence of the Transmit Receive Unit in the Transmit Receive Unit group connects the microprocessor controls unit in the microprocessor controls unit group; Microprocessor controls unit group connects the host microcontroller control module; Storage unit, display unit, host computer interface connect the host microcontroller control module respectively; Reset unit, program burn writing unit, power supply unit of voltage regulation connect host microcontroller control module and microprocessor controls unit group simultaneously; It is characterized in that: microprocessor controls unit group comprises at least two microprocessor controls unit; The Transmit Receive Unit group comprises at least two Transmit Receive Unit, the corresponding Transmit Receive Unit of microprocessor controls unit controls wherein, and Transmit Receive Unit has different configurable rf frequency passages.

2. a kind of multi-microcontroller radio frequency identification read-write device according to claim 1; It is characterized in that: the host microcontroller control module is connected through serial interface bus and common I/O pin with microprocessor controls unit group; The host microcontroller control module is operated in the aggressive mode of serial line interface data transmission, and the microprocessor controls cell operation is at the Passive Mode of serial line interface data transmission.

3. a kind of multi-microcontroller radio frequency identification read-write device according to claim 1 and 2 is characterized in that: the microprocessor controls unit has different serial line interface data transmission priority, and the state of priority is controlled by the host microcontroller control module.

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