The 87C576 includes two separate methods of programming theEPROM array, the traditional modified Quick-Pulse method, and anew On-Board Programming technique (OBP).Quick Pulse programming is a method using a number of devicepins in parallel (see Figure 1) and is the traditional way in which87C51 family members have been programmed. The Quick-Pulsemethod supports the following programming functions:– program USER EPROM– verify USER EPROM– program KEY EPROM– program security bits– verify security bits– read signature bytesThe Quick-Pulse method is quite easily suited to standardprogramming equipment as evidenced by the numerous vendors of87C51 compatible programmers on the market today. Onedisadvantage is that this method is not well suited to programming inthe embedded application because of the large number of signallines that must be isolated from the application. In addition, parallelsignals from a programmer would need to be cabled to theapplication’s circuit board, or the application circuit board wouldneed to have logic built-in to perform the programming functions.These requirements have generally made in-circuit programmingusing the modified Quick Pulse method impractical in almost all87C51 family applications.
上傳時間: 2013-10-21
上傳用戶:xiaozhiqban
Abstract: There are many things to consider when designing a power supply for a field-programmablegate array (FPGA). These include (but are not limited to) the high number of voltage rails, and thediffering requirements for both sequencing/tracking and the voltage ripple limits. This application noteexplains these and other power-supply considerations that an engineer must think through whendesigning a power supply for an FPGA.
上傳時間: 2013-11-10
上傳用戶:iswlkje
This application note describes how to build a system that can be used for determining theoptimal phase shift for a Double Data Rate (DDR) memory feedback clock. In this system, theDDR memory is controlled by a controller that attaches to either the OPB or PLB and is used inan embedded microprocessor application. This reference system also uses a DCM that isconfigured so that the phase of its output clock can be changed while the system is running anda GPIO core that controls that phase shift. The GPIO output is controlled by a softwareapplication that can be run on a PowerPC® 405 or Microblaze™ microprocessor.
上傳時間: 2013-10-15
上傳用戶:euroford
VGA 是視頻圖形陣列(Video Graphics Array)的簡稱,是IBM 于1987 年提出的一個使用模擬信號的圖形顯示標準。最初的VGA 標準最大只能支持640*480 分辨率的顯示器,而為了適應大屏幕的應用,視頻電氣標準化組織VESA(Video Electronics StandardsAssociation 的簡稱)將VGA 標準擴展為SVGA 標準,SVGA 標準能夠支持更大的分辨率。人們通常所說的VGA 實際上指的就是VESA 制定的SVGA 標準。(1). VGA 接口VGA 采用15 針的接口,用于顯示的接口信號主要有5 個:1 個行同步信號、1 個場同步信號以及3 個顏色信號,接口還包含自測試以及地址碼信號,一般由不同的制造商定義,主要用來進行測試及支持其它功能。
上傳時間: 2013-10-27
上傳用戶:541657925
波長信號的解調是實現光纖光柵傳感網絡的關鍵,基于現有的光纖光柵傳感器解調方法,提出一種基于FPGA的雙匹配光纖光柵解調方法,此系統是一種高速率、高精度、低成本的解調系統,并且通過引入雙匹配光柵有效地克服了雙值問題同時擴大了檢測范圍。分析了光纖光柵的測溫原理并給出了該方案軟硬件設計,綜合考慮系統的解調精度和FPGA的處理速度給出了基于拉格朗日的曲線擬合算法。 Abstract: Sensor is one of the most important application of the fiber grating. Wavelength signal demodulating is the key techniques to carry out fiber grating sensing network, based on several existing methods of fiber grating sensor demodulation inadequate, a two-match fiber grating demodulation method was presented. This system is a high-speed, high precision, low-cost demodulation system. And by introducing a two-match grating effectively overcomes the problem of double value while expands the scope of testing. This paper analyzes the principle of fiber Bragg grating temperature and gives the software and hardware design of the program. Considering the system of demodulation accuracy and processing speed of FPGA,this paper gives the curve fitting algorithm based on Lagrange.
上傳時間: 2014-07-24
上傳用戶:caiguoqing
針對物體在不同色溫光源照射下呈現偏色的現象,用FPGA實現對Bayer CCD數字相機的自動白平衡處理。根據CFA(Color Filter Array)的分布特點,利用雙端口RAM(DPRAM),實現了顏色插值與色彩空間轉換。在FPGA上設計了自動白平衡的三大電路模塊:色溫估計、增益計算和色溫校正,并連接形成一個負反饋回路,然后結合EDA設計的特點,改進了增益計算的過程,有效地抑制了色彩振蕩現象。
上傳時間: 2013-10-10
上傳用戶:ouyangmark
Abstract: Communication with 1-Wire slave devices requires a 1-Wire master. There are numerous ways to build a 1-Wire master (see reference design 4206, "Choosing the Right 1-Wire Master for Embedded Applications"). Thisdocument describes the DS1WM, a synthesizable 1-Wire master that can be implemented in an application-specificintegrated circuit (ASIC) or field-programmable gate array (FPGA).
上傳時間: 2014-12-22
上傳用戶:xanxuan
This example provides a description of how to use the USART with hardware flowcontrol and communicate with the Hyperterminal.First, the USART2 sends the TxBuffer to the hyperterminal and still waiting fora string from the hyperterminal that you must enter which must end by '\r'character (keypad ENTER button). Each byte received is retransmitted to theHyperterminal. The string that you have entered is stored in the RxBuffer array. The receivebuffer have a RxBufferSize bytes as maximum. The USART2 is configured as follow: - BaudRate = 115200 baud - Word Length = 8 Bits - One Stop Bit - No parity - Hardware flow control enabled (RTS and CTS signals) - Receive and transmit enabled - USART Clock disabled - USART CPOL: Clock is active low - USART CPHA: Data is captured on the second edge - USART LastBit: The clock pulse of the last data bit is not output to the SCLK pin
上傳時間: 2013-10-31
上傳用戶:yy_cn
AI :Auto-Insertion 自動插件 AQL :acceptable quality level 允收水準 ATE :automatic test equipment 自動測試 ATM :atmosphere 氣壓 BGA :ball grid array 球形矩陣
上傳時間: 2013-11-20
上傳用戶:haoxiyizhong
This application note describes how to build a system that can be used for determining theoptimal phase shift for a Double Data Rate (DDR) memory feedback clock. In this system, theDDR memory is controlled by a controller that attaches to either the OPB or PLB and is used inan embedded microprocessor application. This reference system also uses a DCM that isconfigured so that the phase of its output clock can be changed while the system is running anda GPIO core that controls that phase shift. The GPIO output is controlled by a softwareapplication that can be run on a PowerPC® 405 or Microblaze™ microprocessor.
上傳時間: 2014-11-26
上傳用戶:erkuizhang