針對目前使用的RS232接口數字化B超鍵盤存在PC主機啟動時不能設置BIOS，提出一種PS2鍵盤的設計方法。基于W78E052D單片機，采用8通道串行A/D轉換器設計了8個TGC電位器信息采集電路，電位器位置信息以鍵盤掃描碼序列形式發送，正交編碼器信號通過XC9536XL轉換為單片機可接收的中斷信號，軟件接收到中斷信息后等效處理成按鍵。結果表明，在滿足開機可設置BIOS同時，又可實現超聲特有功能，不需要專門設計驅動程序，接口簡單，成本低。 Abstract: Aiming at the problem of the digital ultrasonic diagnostic imaging system keyboard with RS232 interface currently used couldn?蒺t set the BIOS when the PC boot， this paper proposed a design method of PS2 keyboards. Based on W78E052D microcontroller，designed eight TGC potentiometers information acquisition circuit with 8-channel serial A/D converter， potentiometer position information sent out with keyboard scan code sequentially.The control circuit based on XC9536 CPLD is used for converting the mechanical actions of the encoders into the signals that can be identified by the MCU， software received interrupt information and equivalently treatmented as key. The results show that the BIOS can be set to meet the boot， ultrasound specific functionality can be achieved at the same time， it does not require specially designed driver，the interface is simple and low cost.
上傳時間： 2013-10-10
上傳用戶：asdfasdfd
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.
上傳時間： 2013-10-15
上傳用戶：Ants
首先研究CAN總線和SAE J1939協議，提出一種基于MC9S12HZ256微控制器的總線式汽車數字儀表解決方案。詳細介紹SAE J1939協議的報文幀格式及應用層協議中發動機相關參數的定義，以及步進電機及其驅動和車速信號的處理方法。該數字儀表系統硬件平臺由微處理器和信號采集和信息處理及顯示等模塊組成。軟件設計部分編程實現了對CAN總線和各傳感器數據的讀取、處理。該系統能夠實時反映車輛工況。 Abstract: In this paper，CAN bus and SAE J1939protocol are researched，and a vehicle digital instrument solution based on MC9S12HZ256MCU is proposed.The message frame format and some engine-related parameters’definition in SAE J1939application layer protocol are introduced in detail.Stepper motor and its driver，the methods of speed signal process-ing are also introduced.The hardware platform of vehicle digital instrument is composed by MCU，signal acquisition mod-ule，and signal processing and displaying module.Data receiving and processing from CAN bus and sensors are accom-plished by programming，and vehicle condition can be reflected in real-time.
上傳時間： 2013-10-20
上傳用戶：huannan88
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 。 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.
上傳時間： 2013-11-07
上傳用戶：bs2005
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.
上傳時間： 2013-10-09
上傳用戶：ligi201200
The PCF8578 is a low power CMOS1 LCD row and column driver, designed to drive dotmatrix graphic displays at multiplex rates of 1:8, 1:16, 1:24 or 1:32. The device has40 outputs, of which 24 are programmable and configurable for the following ratios ofrows/columns: 32¤8, 24¤16, 16¤24 or 8¤32. The PCF8578 can function as a stand-alone LCDcontroller and driver for use in small systems. For larger systems it can be used inconjunction with up to 32 PCF8579s for which it has been optimized. Together these twodevices form a general purpose LCD dot matrix driver chip set, capable of driving displaysof up to 40960 dots. The PCF8578 is compatible with most microcontrollers andcommunicates via a two-line bidirectional bus (I2C-bus). Communication overhead isminimized by a display RAM with auto-incremented addressing and display bankswitching.
上傳時間： 2013-10-23
上傳用戶：頂得柱
The SN65LBC170 and SN75LBC170 aremonolithic integrated circuits designed forbidirectional data communication on multipointbus-transmission lines. Potential applicationsinclude serial or parallel data transmission, cabledperipheral buses with twin axial, ribbon, ortwisted-pair cabling. These devices are suitablefor FAST-20 SCSI and can transmit or receivedata pulses as short as 25 ns, with skew lessthan 3 ns.These devices combine three 3-state differentialline drivers and three differential input linereceivers, all of which operate from a single 5-Vpower supply.The driver differential outputs and the receiverdifferential inputs are connected internally to formthree differential input/output (I/O) bus ports thatare designed to offer minimum loading to the buswhenever the driver is disabled or VCC = 0. Theseports feature a wide common-mode voltage rangemaking the device suitable for party-lineapplications over long cable runs.
上傳時間： 2013-10-13
上傳用戶：ytulpx
議程1.瑞薩汽車業務概述2.儀表盤MCU解決方案3.CAN/LIN（車身）MCU解決方案
上傳時間： 2013-10-20
上傳用戶：王成林。
選擇了芯片后，就可以圍繞該芯片確定相應的開發工具。開發工具的好壞往往是決定一個系統成敗的關鍵，下面是對CAN-BUS開發系統組成的一些建議：
上傳時間： 2013-11-02
上傳用戶：yueguizhilin
采用Infineon XC2000系列單片機實現CAN網關模塊，利用MFC編寫PC端網關配置軟件。該系列單片機MultiCAN模塊可實現不同速率的獨立CAN網絡之間的數據接收、存儲、轉發；能夠過濾不需要的CAN消息，降低子網的負荷。該網關模塊可以實現改變CAN網絡拓撲結構、延長網絡通信距離、增加節點數目等功能。
上傳時間： 2014-12-27
上傳用戶：風為裳的風
