CN208094574U - A kind of interface convertor of usb bus and high-speed CAN bus - Google Patents

Abstract

The utility model is related to vehicle bus network fields, and in particular to the design of a kind of usb bus and the interface convertor of high-speed CAN bus.The utility model uses modularized design, includes mainly：Main control module, high-speed CAN bus network module, usb interface module and power module.Main control module circuit is formed using the STM32F103RBT6 chips and its peripheral circuit of ST companies, STM32F103RBT6 possesses abundant Resources on Chip, high-speed CAN bus network module, usb interface module are connected with main control module respectively, and the control function to modules can be realized by main control module.Specially main control module is communicated by the ports I/O with usb interface module, and main control module is communicated by the CAN interface of Resources on Chip with high-speed CAN bus network module.Realize being in communication with each other for data.

Description

A kind of interface converter of USB bus and high-speed CAN bus

technical field

The utility model relates to the field of vehicle-mounted bus networks, in particular to the design of an interface converter between a USB bus and a high-speed CAN bus.

Background technique

CAN bus network technology has been widely used in the field of vehicle network communication due to its characteristics of long transmission distance, high reliability, strong real-time performance and flexible design. Through the CAN bus network, the data interaction between the electronic control units can be completed, and data sharing can be realized, which greatly improves the modularization ability of the whole vehicle, and can flexibly design and configure the vehicle system, and finally improve the overall performance of the vehicle, such as power and economy. sex and safety etc.

In recent years, with the continuous development of technology, the USB bus technology has been promoted from the original 1.1 full-speed version to the 2.0 high-speed version. With the addition of USB-OTG technology, it is similar to the PCI bus and has fast, two-way, plug and play and low price. The low-cost USB bus technology brings great convenience to users. It meets people's requirements for bus ease of use, strong expansion capability and low cost, and has gradually become one of the most important peripheral interfaces of PCs.

Although the characteristics of the above two buses are quite prominent, their application in the field of control still has its own limitations. With the rapid development of vehicle bus technology, the standard CAN bus is difficult to meet the real-time control and communication bandwidth requirements of modern vehicles due to its low speed (below 1Mbps); and the connection between the CAN adapter and the host on the traditional interface is very cumbersome and complicated. Conducive to the application expansion of CAN. However, the number of devices that can be connected to the USB bus is small, the communication distance is short, and the anti-interference ability is weak and other factors cannot meet the requirements of industrial applications; at the same time, the USB communication protocol is complicated. The process of relatively complex configuration and channel establishment cannot be realized with simple logic circuits. Increased the difficulty of developers. Therefore, how to combine the high-speed CAN bus with the USB bus and make full use of the advantages of both, so that it can achieve more powerful and flexible communication functions in the field of field measurement and control, has become a problem that needs to be solved in the vehicle network.

Contents of the invention

The utility model provides an interface converter for a USB bus and a high-speed CAN bus network for the above-mentioned problems. interconnected. In order to achieve the above functions, the utility model adopts a modular design, as shown in Figure 1, which mainly includes: a main control module, a high-speed CAN bus network module, a USB interface module and a power supply module. The high-speed CAN bus network module and the USB interface module are respectively connected with the main control module, and the control function of each module can be realized through the main control module.

The main control module circuit adopts the STM32F103RBT6 chip of ST Company and its peripheral circuits. The STM32F103RBT6 has abundant resources on the chip, communicates with the USB interface module through the I/O port, and communicates with the high-speed CAN bus network module through the CAN interface on the chip. Realize mutual communication of data.

The high-speed CAN bus module is composed of the CAN protocol controller in the STM32F103RBT6 chip and the high-speed CAN transceiver TJA1052i chip released by NXP Semiconductors. TJA1052i integrates an isolator and a high-speed CAN transceiver, which not only simplifies the isolation design work between high and low voltages, reduces circuit board space, reduces costs, but also improves signal performance and system stability.

Described USB interface module adopts the high-speed USB interface chip CY7C68013A of Cypress Company, and this chip interior mainly comprises high-performance microprocessor core, USB2. FIFO, I/O interface, data bus, address bus, I2C master controller and general programmable interface, etc. It is a representative interface chip of high-performance high-speed USB 2.0 at present, and the chip is connected with the main control chip through the I/O port.

Compared with the prior art, first of all, the utility model adopts a modular design, which is convenient for program debugging, modification, transplantation and the expansion and development of subsequent function programs; secondly, the main control module of the utility model adopts the STM32F103RBT6 chip, which has rich On-chip resources, the main control module can be connected to the USB interface module and the high-speed CAN transceiver module at the same time, which can make the connection between the modules simple and convenient, and save costs; at the same time, the use of STM32F103RBT6 can make the system performance more stable and reliable. Finally, the utility model realizes the mutual communication between the CAN bus network and the USB bus, can make full use of the advantages of the two, and is widely used in the field of on-site measurement and control to realize more powerful and flexible communication functions.

Description of drawings

Fig. 1 is a functional block diagram of the utility model.

Fig. 2 is the master control module of the present utility model.

Fig. 3 is the high-speed CAN bus network module of the present utility model.

Fig. 4 is the USB interface module of the present invention.

Fig. 5 is the power module of the present utility model.

Detailed ways

In order to make the purpose, technical solution and advantages of the present utility model clearer, the technical solution of the present utility model will be further described in detail below in conjunction with the accompanying drawings.

The utility model adopts a modular design, as shown in Figure 1, it is mainly composed of a main control module, a high-speed CAN bus network module, a USB interface module and a power supply module. Among them, the main control module adopts the STM32F103RBT6 chip of ST Company. The main control module is connected with the high-speed CAN bus network module and the USB interface module respectively. The control function of each module can be realized through the main control module. The control commands can be sent to the high-speed CAN bus network, and the high-speed CAN bus network data can also be sent to the host computer through the USB interface module. Specifically, the main control module is connected to the USB interface module through the I/O port, and the main control module is connected to the high-speed CAN bus network module through the CAN interface to realize mutual data communication between the two. The power supply module supplies power to the main control module, USB interface module and high-speed CAN bus module.

The main control module U1 is mainly composed of the STM32F103RBT6 chip and its peripheral circuits: as shown in Figure 2, it mainly includes a power-down protection circuit composed of BT1, D1, D2, and Y1, which supplies power for the real-time clock when the system is powered off and in low-power consumption mode. The reset circuit composed of S1, C1 and R1 realizes the CPU reset function when the S1 button is pressed; the oscillation circuit composed of R2, Y2, C2 and C3 provides a clock for the CPU; the filter circuit composed of C4, C5 and L1 The power supply of the A/D converter inside the chip is decoupled and filtered; the pins 18 and 19 of U1 are connected with C6 to form a decoupling circuit, and the pins 31 and 32 of U1 are connected with C7 to form a decoupling circuit. Pins 47 and 48 are connected to C8 to form a decoupling circuit, and pins 63 and 64 of U1 are connected to C9 to form a decoupling circuit, mainly to remove power supply noise and improve the anti-interference ability of the CPU; R3 and R4 are used as current limiting resistors , and light-emitting diodes LED1 and LED2 form a circuit to indicate the serial port data transmission and reception, that is, LED1 is on when there is data transmission, and LED2 is on when there is data reception, otherwise it is not on. The main control module is connected to the USB interface module CY7C68013A through the I/O port of its on-chip resources, and connected to the high-speed CAN bus module through its on-chip CAN interface to realize the communication between the USB bus and the high-speed CAN bus network. Specifically, the lead of the main control module U1 The pins PA0~PA7 are respectively connected with the pins PB0~PB7 of the USB interface module CY7C68013A. The main control module U1 is electrically connected to the pins TXD and RXD of the high-speed CAN bus network module through the pins CAN_TX and CAN_RX respectively.

The high-speed CAN bus interface module is composed of a CAN controller and a high-speed CAN transceiver module. The CAN controller adopts the CAN controller of the on-chip resource of the main control module. The high-speed CAN transceiver module U2 selects the TJA1052i chip launched by NXP Semiconductors. TJA1052i is very suitable In the CAN network that requires the coexistence of high and low voltages, TJA1052i integrates an isolator and a high-speed CAN transceiver, which not only simplifies the isolation design between high and low voltages, reduces costs, but also improves signal performance , System stability. As shown in Figure 3, the acquisition and transmission of data on the CAN bus can be realized through this module. Specifically, the module is connected to the CAN_TX and CAN_RX pins of the main control module through the pins TXD and RXD respectively, and the pin CANH of the module A 120-ohm terminal resistor R5 is connected between CANL and CANL to improve the safety and reliability of the circuit, and then it can be connected to the high-speed CAN bus network.

The USB interface module U3 adopts Cypress's high-speed USB interface chip CY7C68013A, which mainly includes high-performance microprocessor core, USB2.0 transceiver, intelligent engine (SIE), enhanced 8051 core, 16K RAM, 4K FIFO, I/O interface, data bus, address bus, I2C master controller and general programmable interface, etc. It is a representative interface chip of high-performance high-speed USB2.0. As shown in Figure 4, the pins PB0~PB7 of the chip are respectively connected to the pins PA0~PA7 of the main control chip STM32F103RBT6 to transmit data; the pin SLOE is connected to the pin PB10 of the main control module to control the USB To read the data in the chip, when reading the data in the USB chip, set this pin low; the pin SLWR is connected to the PB11 of the main control module, which means that the external data needs to be written into the USB chip; the pins XTALOUT, XTALIN is connected to the clock circuit composed of Y3, C10 and C11 to provide clock for the system; the pins FLAGB and FLAGC are respectively connected to the pins PB0 and PB1 of the main control module to indicate the status of the corresponding buffer, so that the host can The USB chip performs corresponding operations; through the pins DPLUS and DMINUS, it is connected to the USB interface, and can be connected to the PC through the USB interface.

The circuit of the power module is shown in Figure 5. The power module provides the required power for other units. The system is powered by a 5V power supply, and the chip power requirement of the terminal part is 3.3V, so the power supply becomes 3.3V after the current regulator chip REG1117-3.3 V voltage, power supply for CPU and USB circuit, in order to ensure that 5V power supply and 3.3V do not affect each other, D050505T is a DC/DC isolated power supply, which is used to supply power to high-speed CAN circuit to realize bus isolation.

Concrete workflow of the present utility model is as follows:

After power-on, initialize the main control module, high-speed CAN bus network module, USB interface module, etc., configure parameters for each module, and then start data communication.

When the CAN bus has data to upload to the PC, the CAN bus first packs the data and sends it to the high-speed CAN transceiver module TJA1052i, and the high-speed CAN transceiver module sends the CAN data frame to the main control module through the CAN controller interface of the main control module. After the module, the main control module parses the received CAN data through the protocol and packs it into a USB data frame, and sends the data to the USB bus through the USB interface module, and then sends the data to the PC.

When the PC has data to send, the USB interface module CY7C68013A receives the USB data frame, the USB interface module sends the data to the main control module through the I/O port, and the main control module parses the received data through the protocol and packs it into After the CAN data is formatted, the data is sent to the CAN network bus through the CAN controller of its own on-chip resources and the high-speed CAN transceiver module.

Through the interface adapter of the utility model, each communication message and the entire communication process on the bus can be recorded, so as to achieve the purpose of data interaction such as process data, message data, and monitoring data.

Claims (2)

1. A kind of interface converter of USB bus and CAN bus, it is characterized in that: adopt modular design, comprise: main control module, high-speed CAN bus network module, USB interface module and power supply module; Wherein main control module adopts STM32F103RBT6 chip; The high-speed CAN bus module is composed of the CAN protocol controller in the STM32F103RBT6 chip and the high-speed CAN transceiver TJA1052i chip, which is connected with the main control module to realize the data transmission and reception of the high-speed CAN network; /O is connected with the port main control chip to realize the interaction between data and the upper computer. 2. the interface converter of a kind of USB bus and CAN bus according to claim 1 is characterized in that: described main control module circuit adopts STM32F103RBT6 chip of ST Company and peripheral circuit thereof to form, through I/O interface and The USB interface module communicates, and communicates with the high-speed CAN bus network module through the on-chip CAN interface to realize mutual communication of data.