CN207718364U

CN207718364U - A kind of multichannel RS-422 serial ports expansion interfaces based on FPGA

Info

Publication number: CN207718364U
Application number: CN201820032058.8U
Authority: CN
Inventors: 刘涛
Original assignee: CETC 27 Research Institute
Current assignee: CETC 27 Research Institute
Priority date: 2018-01-09
Filing date: 2018-01-09
Publication date: 2018-08-10
Anticipated expiration: 2028-01-09

Abstract

The utility model discloses a kind of 422 serial ports expansion interfaces of multichannel RS based on FPGA, including fpga chip, multiple RS422 interface chips, the receiving terminal and transmitting terminal of any one RS422 interface chip are correspondingly connected with one I/O mouthfuls of FPGA by conversion chip respectively, fpga chip is connected by bus with host computer, the bus includes address bus and data/address bus, the two parallel connection.The utility model by using FPGA I/O mouths, connect the sending and receiving end of RS422 interface chips, utilize parallel bus and host computer into row data communication simultaneously, realize higher speed, more multichannel serial interface extension, in conjunction with FPGA software programmings serial ports transceiver module may be implemented arbitrary baud rate serial data transmitting-receiving, serial port baud rate can be configured by host computer, easy to use, the high-speed communication of the realization multi-channel serial port and host that can stablize reduces cost simultaneously.

Description

A kind of multichannel RS-422 serial ports expansion interfaces based on FPGA

Technical field

The utility model is related to communication interface technology field more particularly to a kind of multichannel RS-422 serial ports expansions based on FPGA Open up interface.

Background technology

Currently, in communication interface, control is flexible, interface is simple, occupying system resources are few by it for serial interface devices The advantages that, it is widely used in various fields.Especially in embedded systems, usually will appear many equipment to be required for passing through Serial ports is communicated with host, this makes developer usually face the problem of serial communication interface deficiency.Currently, for above-mentioned The common solution of problem has software simulation method and is extended serial ports using proprietary extensions chip.But software simulation method Although implementing simply, in actual use, stability bottom, poor reliability；And it is carried out by proprietary extensions chip monolithic In the method for extended serial port, the negligible amounts for the serial ports that can be extended, to which most use demands cannot be met.

Utility model content

The purpose of this utility model is to provide a kind of multichannel RS-422 serial ports expansion interfaces based on FPGA, can stablize Realize the high-speed communication of multi-channel serial port and host.

The technical solution adopted in the utility model is：

A kind of multichannel RS-422 serial ports expansion interfaces based on FPGA, including fpga chip, multiple RS422 interface chips, The receiving terminal and transmitting terminal of any one RS422 interface chip are correspondingly connected with an I/O of FPGA by conversion chip respectively Mouthful, fpga chip is connected by bus with host computer, and the bus includes address bus and data/address bus, and the two connects parallel It connects.

The conversion chip is MAX3490.

Further include having multiple FIFO memory buffers chips, the single FIFO memory buffers chip-in series are in conversion chip And between one I/O mouthfuls of FPGA.

The FIFO memory buffers chips use AL422B.

The utility model connects the sending and receiving end of RS422 interface chips, while using parallel by using the I/O mouths of FPGA Bus, into row data communication, realizes higher speed, the serial interface extension of more multichannel, in conjunction with the string of FPGA software programmings with host computer The transmitting-receiving of the serial data of arbitrary baud rate may be implemented in mouth transceiver module, and serial port baud rate can be matched by host computer It sets, easy to use, the high-speed communication of the realization multi-channel serial port and host that can stablize reduces cost simultaneously, has larger push away Wide value.

Description of the drawings

Fig. 1 is the schematic block circuit diagram of the utility model.

Specific implementation mode

As shown in Figure 1, the utility model includes fpga chip, multiple RS422 interface chips, any one described RS422 connects The receiving terminal and transmitting terminal of mouth chip are correspondingly connected with one I/O mouthfuls of FPGA by conversion chip respectively, and fpga chip passes through total Line is connected with host computer, and the bus includes address bus and data/address bus, the two parallel connection.

The conversion chip is MAX3490, can be carried out at the same time transmitting-receiving action.

The realization method of the technology is further described with reference to above-mentioned attached drawing.

RS422 rs 232 serial interface signals are converted to RS232 signals by conversion chip, are transferred to the I/O mouths of FPGA.By software UART transceiver modules send serial data to data processing module.String property data are converted to parallel data by data processing module, Data are identified from which serial ports by address bus, host computer is sent data to by data/address bus.So far, Receive process are finished.

Transmission process is then sent data and the serial ports way to be sent by data/address bus and address bus by host computer To FPGA, serial data is converted parallel data into soon via data processing mould, is judged from which according to the data of address bus Road serial ports is sent out.So far, transmission process is finished.

Higher speed may be implemented compared to serial ports expansion serial ports, using parallel bus extended serial port in the utility model, more The serial interface on road extends.Using the I/O mouths of FPGA, connect the sending and receiving end of RS422 interface chips, at the same using parallel bus with Host computer is into row data communication.The receipts of the serial data of arbitrary baud rate may be implemented in the serial ports transceiver module of FPGA software programmings Hair, serial port baud rate can be configured by host computer, easy to use.The reliable of high-speed transfer can be ensured by introducing FIFO, The throughput of data is improved, while data being avoided to be lost because not having timely processing.Data processing module is then used for realizing string simultaneously It converts, and identifies the way of each circuit-switched data by data/address bus, the bus communication of control and host computer.

The utility model patent is not take up system extra resource compared to software simulation method extended serial port, can be reliably Realize that the extension of high-speed serial data receives.The I/O of FPGA can be used compared to special serial port extended chip, this patent is utilized Cause for gossip shows multi-channel serial port extension, and extended capability is far longer than single special chip.

Claims

1. a kind of multichannel RS-422 serial ports expansion interfaces based on FPGA, it is characterised in that：Including fpga chip, multiple RS422 Interface chip, the receiving terminal and transmitting terminal of any one RS422 interface chip are correspondingly connected with FPGA by conversion chip respectively One I/O mouthfuls, fpga chip is connected by bus with host computer, and the bus includes address bus and data/address bus, two Person is connected in parallel.

2. the multichannel RS-422 serial ports expansion interfaces according to claim 1 based on FPGA, it is characterised in that：Described turns It is MAX3490 to change chip.

3. the multichannel RS-422 serial ports expansion interfaces according to claim 2 based on FPGA, it is characterised in that：Further include having Multiple FIFO memory buffers chips, an I/O of the multiple FIFO memory buffers chip-in series in conversion chip and FPGA Between mouthful.

4. the multichannel RS-422 serial ports expansion interfaces according to claim 3 based on FPGA, it is characterised in that：Described FIFO memory buffers chips use AL422B.