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.
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.
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.
波長(zhǎng)信號(hào)的解調(diào)是實(shí)現(xiàn)光纖光柵傳感網(wǎng)絡(luò)的關(guān)鍵，基于現(xiàn)有的光纖光柵傳感器解調(diào)方法，提出一種基于FPGA的雙匹配光纖光柵解調(diào)方法，此系統(tǒng)是一種高速率、高精度、低成本的解調(diào)系統(tǒng)，并且通過(guò)引入雙匹配光柵有效地克服了雙值問(wèn)題同時(shí)擴(kuò)大了檢測(cè)范圍。分析了光纖光柵的測(cè)溫原理并給出了該方案軟硬件設(shè)計(jì)，綜合考慮系統(tǒng)的解調(diào)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.
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).
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
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.
