CN110311697B

CN110311697B - Remote data concentrator

Info

Publication number: CN110311697B
Application number: CN201910564030.8A
Authority: CN
Inventors: 陈栋; 吉沛琦; 谭永亮; 李修杰; 袁泉
Original assignee: China Aeronautical Radio Electronics Research Institute
Current assignee: China Aeronautical Radio Electronics Research Institute
Priority date: 2019-06-24
Filing date: 2019-06-24
Publication date: 2021-07-09
Anticipated expiration: 2039-06-24
Also published as: CN110311697A

Abstract

The invention discloses a remote data concentrator, which comprises ARINC429 data receiving logic, an ARINC429 receiving FIFO, an ARINC429 double-port BRAM and a data flow direction control module, wherein the ARINC429 data receiving logic is used for storing a data frame into the ARINC429 receiving FIFO; the data flow direction control module is used for judging whether an ARINC429 data frame exists in an ARINC429 receiving FIFO or not, if so, reading the data frame, storing the data into a corresponding cache address of an ARINC429 double-port BRAM according to a tag number in the data frame, and giving out an identifier that the corresponding tag number has the data to upper-layer software; when the data flow direction control module receives a data frame request of upper layer software to a certain label number, the data frame is read from the corresponding cache address of ARINC429 double-port BRAM and transmitted to the upper layer software. The invention shortens the forwarding time of the upper layer software.

Description

Remote data concentrator

Technical Field

The invention relates to the field of avionic products, in particular to a remote data concentrator, which improves the data forwarding efficiency by changing a cache structure.

Background

Remote Data Concentrators (RDCs), originally proposed by boeing, are currently widely used in avionics systems, such as civil aircraft and transport aircraft, and both a380 and B737 use this technology. In the context of the highly integrated avionics (IMA architecture) of aircraft, more and more aircraft employ remote data interface units as important data nodes at various locations throughout the aircraft, which replace conventional dedicated signal lines and facilitate device separation, minimize the wiring and weight of subsystems, sensors and effectors, facilitate system updates, and are of great significance in the aspects of reliability, maintainability, versatility, etc. of the aircraft system.

The RDC product includes ARINC429 and ARINC825 communication interfaces, and when receiving data, the bottom layer FPGA logic temporarily buffers the received data in the FPGA for the CPU software to read.

The ARINC429 has multiple paths of data receiving, each path of received data corresponds to ARINC429 data with multiple label numbers, and a path is required to be transmitted according to a certain period in the forwarding requirement of the RDC product

Certain label number data in ARINC429 data are forwarded. Referring to fig. 1, the conventional RDC product only allocates one FIFO buffer for each way of ARINC429 data, which increases the difficulty for the upper layer software to obtain a specific label number data at a certain time.

The same ARINC825 also has multiplex transmission, each path of received data corresponds to ARINC825 data with a plurality of ID numbers, and a path of received data is required to be transmitted according to a certain period in the forwarding requirement of RDC products

Data of a specific ID number in ARINC825 data is forwarded. The traditional RDC product only configures one FIFO buffer for each way of ARINC825 data, which increases the difficulty of CPU software to obtain a certain ID number data at a certain time.

Civil aircrafts C919 independently designed in China largely use remote data interface units, but all the products are derived from foreign shelf products and have opaque internal design, which is not beneficial to independent controllability of the aviation industry. The invention relies on a certain civil transport project, designs and realizes a high-reliability, strong-universality and configurable remote data interface unit on the premise that the integral avionics system adopts an IMA architecture, and realizes real-time conversion and forwarding among various data.

Disclosure of Invention

The invention aims to provide a remote data concentrator, which enables upper-layer application software to acquire data in time by perfecting bottom-layer logic, reduces the complexity and scheduling of the application software, shortens the forwarding time of the application software and improves the forwarding performance of RDC products.

The invention aims to be realized by the following technical scheme:

a remote data concentrator comprises an ARINC429 logic module, an ARINC429 logic module comprises a plurality of ARINC429 receiving modules, each ARINC429 receiving module is used for receiving one path of ARINC429 data, the ARINC429 receiving module comprises ARINC429 data receiving logic, an ARINC429 receiving FIFO, an ARINC429 double-port BRAM and a data flow direction control module;

ARINC429 data receiving logic is used for receiving ARINC429 data frames from an ARINC429 bus and storing the ARINC429 data frames into an ARINC429 receiving FIFO;

the ARINC429 double-port BRAM is divided into a plurality of buffers, and each buffer address corresponds to a tag number in an ARINC429 data frame;

the data flow direction control module is used for judging whether an ARINC429 data frame exists in an ARINC429 receiving FIFO or not, if yes, reading the ARINC429 data frame, storing data into a corresponding cache address of an ARINC429 double-port BRAM according to a tag number in the ARINC429 data frame, and giving a mark that the corresponding tag number has the data to upper-layer software; when the data flow direction control module receives an ARINC429 data frame request of upper-layer software to a certain label number, the ARINC429 data frame is read from a corresponding cache address of the ARINC429 double-port BRAM and is transmitted to the upper-layer software.

The ARINC429 logic module also comprises an ARINC429 transmitting module, the ARINC429 transmitting module comprises an ARINC429 transmitting FIFO and ARINC429 data transmitting logic, and the ARINC429 data transmitting logic is used for firstly judging whether an ARINC429 data frame stored by upper-layer software exists in the ARINC429 transmitting FIFO or not, and if so, reading and transmitting the data frame to an ARINC429 bus.

The remote data concentrator also comprises an ARINC825 communication module, wherein the ARINC825 communication module comprises an ARINC825 receiving data control module, a receiving status register and an ARINC825 dual-port BRAM;

the ARINC825 dual-port BRAM is divided into a plurality of buffers, and each buffer address is used for storing a CAN extended frame;

the ARINC825 receives a data control module to fill a CAN extended frame received from an external protocol chip into a cache address in an ARINC825 dual-port BRAM, and a register mark corresponding to the cache address in a receiving status register is marked to have data and an ID number filled in the CAN extended frame; when the upper layer software takes data from a certain cache address in the receiving cache dual-port BRAM, the ARINC825 receiving data control module marks a register corresponding to the cache address in the receiving status register as no data.

The ARINC825 communication module also comprises an ARINC825 transmission data control module and an ARINC825 transmission data buffer FIFO;

the ARINC825 data transmission control module is used for firstly judging whether CAN extended frames stored by upper-layer software exist in an ARINC825 data transmission cache FIFO or not, and if yes, reading and transmitting the CAN extended frames to an external protocol chip.

The invention has the beneficial effects that:

the invention provides a design realization method and an idea for functions of the intelligent RDC and other remote interface products, and has stronger universality on the premise of ensuring reliability and safety. The ARINC429 logic module and the ARINC825 communication module are used as bottom-layer logic to perfect the logic modules, so that the data can be acquired by upper-layer application software in time, the complexity and the scheduling of the application software are reduced, the forwarding time of the application software is shortened, and the forwarding performance of an RDC product is improved.

Drawings

Fig. 1 is a schematic diagram illustrating a transceiving principle of an ARINC429 interface in a conventional remote data concentrator.

Fig. 2 is a schematic block diagram of a single-way ARINC429 reception in a remote data concentrator in accordance with an embodiment.

Fig. 3 is a schematic block diagram of multiple ARINC429 reception in a remote data concentrator in accordance with an embodiment.

Fig. 4 is a schematic block diagram of ARINC825 transceiving in the remote data concentrator according to the embodiment.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples.

The underlying modules of the remote data concentrator shown in this embodiment include ARINC429 logic modules and ARINC825 communications modules.

The ARINC429 logic module comprises a plurality of ARINC429 receiving modules, as shown in fig. 2, each ARINC429 receiving module is used for receiving one path of ARINC429 data, and the ARINC429 receiving module comprises ARINC429 data receiving logic, an ARINC429 receiving FIFO, an ARINC429 dual-port BRAM and a data flow direction control module.

The ARINC429 data receiving logic is configured to receive the ARINC429 data frame on the ARINC429 bus and store the ARINC429 data frame into the ARINC429 receive FIFO.

The ARINC429 double-port BRAM is internally divided into 256 address buffer areas according to the label number (label number) of each way of ARINC429, the size of each buffer area is 16, and each buffer address corresponds to one label number in sequence.

For upper-layer software, it can be seen that 256 fifo with a depth of 16 are set inside the ARINC429 logic module for each channel, and each fifo corresponds to data of one cable number.

When instantiating the multi-path ARINC429 receiving module, the logic design block diagram is as shown in fig. 3, a channel switching module is added at the interface with the AXI bus, and upper layer software can switch and read the data flag of each path through the channel switching module, so as to enable the label number which is supposed to be read, to read the data of different label numbers of different channels.

The entire ARINC429 receive logic module may be configured to receive data by channel number or by label number.

The ARINC429 logic module also comprises an ARINC429 transmitting module, the ARINC429 transmitting module is similar to a traditional ROC product and comprises an ARINC429 transmitting FIFO and ARINC429 data transmitting logic, and the ARINC429 data transmitting logic is used for judging whether an ARINC429 data frame stored by upper-layer software is arranged in the ARINC429 transmitting FIFO or not, and reading and transmitting the data frame to an ARINC429 bus if the ARINC429 data frame is arranged in the ARINC429 transmitting FIFO.

Design block diagram of ARINC825 communication module as shown in fig. 4, the ARINC825 communication module comprises an ARINC825 receiving data control module, a receiving status register and ARINC825 dual port BRAM, an ARINC825 transmitting data control module and an ARINC825 transmitting data buffer FIFO.

The ARINC825 communication module supports two modes of operation. The selection may be configured by an upper layer software write command.

In the first mode, the upper layer software can control the SJA1000 protocol chip in real time. The ARINC825 communication module only performs read-write time sequence processing on the control signal, and ensures that no problem exists in reading and writing data between upper-layer software and a protocol chip.

In the second mode, the ARINC825 communication module directly controls the protocol chip to transmit and receive data, and upper-layer software buffers the data to be transmitted and received in the ARINC825 communication module. Firstly, after being powered on, an ARINC825 communication module works in a first mode by default, and upper-layer software directly controls a protocol chip to carry out initialization operation; then the upper software sets up the logic to switch over to under the second kind of mode; when data is to be sent, the main control software fills data to be sent into an ARINC825 data sending buffer FIFO (bit width 104bit, depth 32) according to a fixed format, the ARINC825 data sending control module firstly judges whether the ARINC825 data sending buffer FIFO has a CAN extended frame stored in upper layer software, and if the CAN extended frame exists, the data is read out and sent to an external protocol chip. When receiving data, the ARINC825 receiving data control module fills the CAN extended frame received from the external protocol chip into a cache address in the ARINC825 dual-port BRAM; the ARINC825 double-port BRAM defines 50 cache addresses, each cache address has a data bit width of 104 bits and CAN support the storage of a complete CAN extended frame, when a certain cache address is filled with data, the ARINC825 receives the register mark of the data control module corresponding to the cache address in the receiving state register and is marked to have data and an ID number filled with the CAN extended frame; when the upper layer software takes data from a certain cache address in the receiving cache dual-port BRAM, the ARINC825 receiving data control module marks a register corresponding to the cache address in the receiving status register as no data.

It should be understood that equivalents and modifications of the technical solution and inventive concept thereof may occur to those skilled in the art, and all such modifications and alterations should fall within the scope of the appended claims.

Claims

1. A remote data concentrator comprises an ARINC429 logic module and an ARINC825 communication module, wherein the ARINC429 logic module comprises a plurality of ARINC429 receiving modules, each ARINC429 receiving module is used for receiving one path of ARINC429 data, and the ARINC825 communication module comprises an ARINC825 receiving data control module, a receiving status register and an ARINC825 dual-port BRAM; the method is characterized in that:

the ARINC429 receiving module comprises ARINC429 data receiving logic, an ARINC429 receiving FIFO, an ARINC429 double-port BRAM and a data flow direction control module, wherein the ARINC429 data receiving logic is used for receiving an ARINC429 data frame from an ARINC429 bus and storing the ARINC429 data frame into the ARINC429 receiving FIFO;

the data flow direction control module is used for judging whether an ARINC429 data frame exists in an ARINC429 receiving FIFO or not, if yes, reading the ARINC429 data frame, storing data into a corresponding cache address of an ARINC429 double-port BRAM according to a tag number in the ARINC429 data frame, and giving a mark that the corresponding tag number has the data to upper-layer software; when the data flow direction control module receives an ARINC429 data frame request of upper-layer software to a certain label number, reading an ARINC429 data frame from a corresponding cache address of an ARINC429 double-port BRAM and transmitting the ARINC429 data frame to the upper-layer software;

2. The remote data concentrator as claimed in claim 1 wherein the ARINC429 logic module further comprises an ARINC429 transmit module, the ARINC429 transmit module comprises an ARINC429 transmit FIFO and ARINC429 data transmit logic, the ARINC429 data transmit logic being configured to first determine whether there is an ARINC429 data frame stored in the ARINC429 transmit FIFO by upper layer software, and if so, to read and transmit the data frame to the ARINC429 bus.

3. The remote data concentrator as claimed in claim 1 wherein the ARINC825 communications module further comprises an ARINC825 transmit data control module and an ARINC825 transmit data buffer FIFO;