CAN-Bus(Corltroller Area Network)即控制器局域網,是國際上應用最廣泛的現場總線之一。它是一種多主方式的串行通訊總線,在工業控制通訊方面擁有高位速率,高抗電磁干擾性,而且能夠檢測出產生的任何錯誤。作為一種靈活,可靠的通訊系統,CAN總線已被廣泛運用于各個工業控制現場。 基于FPGA+DSP的CAN總線通訊系統設計主要目標是完成CAN總線的多節點可靠高速性傳輸,通過各節點之間的數據通信以及結點處理單元內部對數據的處理實現整個通信系統間各個單元的協同工作。 本論文中的 CAN 總線通訊系統是完成紅外目標探測系統和控制系統與圖像處理系統的實時通信,其硬件部分采用 DSP+FPGA 作為核心通訊處理單元,通過對 DSP硬件編程和FPGA邏輯模塊的設計實現了在處理單元外部CAN總線多節點之間的信息可靠性傳輸以及處理單元內部DSP和FPGA基于SPI的串行通信,從而完成了在FPGA中對CAN總線數據的處理和運用。
以太網和CAN總線應用廣泛,但由于其通信協議不同,兩種總線器件間無法進行數據通信,因此,設計了基于CP2200與C8051F040的以太網總線與CAN總線接口轉換電路,并給出部分相關硬件電路與軟件設計分析。在保證數據完整和協議可靠的前提下,通過握手協議和簡化的以太網協議,不僅實現了以太網數據與CAN數據的轉發,同時還順利的解決了以太網的高速性與CAN的低速率沖突,以及兩者數據包之間的大小不同的矛盾。
Abstract: In the development of actual application, Ethernet and CAN bus are used very extensively. Owing to its various communication protocols, the communicating between two kinds of bus device can’t be carried out. Therefore, in order to solve this problem, the Ethernet-CAN bus interface circuit based on CP2200 and C8051F040 was designed in this paper, and part of the related hardware circuit and software design analysis were given. On the condition of data’s integrity and protocols’reliability, through the handshaking protocols and the simplified the Ethernet protocol, not only the data switching between CAN and Ethernet was realized, but also the differ in velocity and packet size was solved.
介紹一種基于CAN總線的牽引變電站自動化系統通訊規約的設計,CAN通訊規約采用標準幀,報文采用主動發送和發送查詢兩種處理形式。該設計在城市輕軌與地鐵牽引變電站中的應用表明:可實現間隔層和通訊處理層的數據快速、可靠的交換,提高牽引變電站的安全性和穩定性
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Abstract:
This paper firstly presents a kind of design dealing with communicational protocol to the traction substation automation system based on CAN bus,and then comes up with the ideas that all frames of CAN communicational protocol should adopt the standard frame,and that messages be processed by two ways:sending initiatively and sending quiries.Subway and light rail application shows that the use of the CAN bus is possible to exchange data quickly and reliably between the layers of the middle and the communicational processing,hence to improve the safety and stability of traction substations.
對于瀝青混凝土攤鋪機自動找平控制系統來說,數字式控制系統的研制是目前的一個方向。介紹了一種基于CAN總線的數字式自動找平控制系統。該系統以CAN總線作為通信方式,PWM控制信號通過C8051F040單片機內部PCA可編程計數器陣列產生,并具有結構簡單、信號穩定、實時性強、易擴展的特點。通過硬件實現和系統運行達到了比較理想的控制效果,驗證了系統的可行性。
Abstract:
A digital auto-leveling control system based on CAN Bus is introduced.It uses CAN Bus as the method of communication and creates PWM signals by programmable counter array in C8051F040 microcontroller. The system is simple, stable, real-time and expansive.