針對UHF讀寫器設(shè)計中，在符合EPC Gen2標(biāo)準的情況下，對標(biāo)簽返回的高速數(shù)據(jù)進行正確解碼以達到正確讀取標(biāo)簽的要求，提出了一種新的在ARM平臺下采用邊沿捕獲統(tǒng)計定時器數(shù)判斷數(shù)據(jù)的方法，并對FM0編碼進行解碼。與傳統(tǒng)的使用定時器定時采樣高低電平的FM0解碼方法相比，該解碼方法可以減少定時器定時誤差累積的影響；可以將捕獲定時器數(shù)中斷與數(shù)據(jù)判斷解碼相對分隔開，使得中斷對解碼影響很小，實現(xiàn)捕獲與解碼的同步。通過實驗表明，這種方法提高了解碼的效率，在160 Kb/s的接收速度下，讀取一張標(biāo)簽的時間約為30次/s。
Abstract:
Aiming at the requirement of receiving correctly decoded data from the tag under high-speed communication which complied with EPC Gen2 standard in the design of UHF interrogator， the article introduced a new technology for FM0 decoding which counted the timer counter to judge data by using the edge interval of signal capture based on the ARM7 platform. Compared with the traditional FM0 decoding method which used the timer timed to sample the high and low level， the method could reduce the accumulation of timing error and could relatively separate capture timer interrupt and the data judgment for decoding， so that the disruption effect on the decoding was small and realizd synchronization of capture and decoding. Testing result shows that the method improves the efficiency of decoding， at 160 Kb/s receiving speed， the time of the interrogator to read a tag is about 30 times/s.
ARM核心是主控SOC中的重要部分，系統(tǒng)的日常應(yīng)用都由ARM核心來完成，因此ARM核心的效能很大程度上跟用戶體驗有關(guān)。ARM公司一般用DMIPS/MHz來標(biāo)稱ARM核心的性能。DMIPS是Dhrystone Million Instructions executed Per Second的縮寫，反映核心的整數(shù)計算能力。但Dhrystone算法代碼本身比較叫，可以完全放到Cache中執(zhí)行，因此反映的只是核心能力，并不能反映緩存、內(nèi)存I/O性能。
The LPC1850/30/20/10 are ARM Cortex-M3 based microcontrollers for embeddedapplications. The ARM Cortex-M3 is a next generation core that offers systemenhancements such as low power consumption, enhanced debug features, and a highlevel of support block integration.The LPC1850/30/20/10 operate at CPU frequencies of up to 150 MHz. The ARMCortex-M3 CPU incorporates a 3-stage pipeline and uses a Harvard architecture withseparate local instruction and data buses as well as a third bus for peripherals. The ARMCortex-M3 CPU also includes an internal prefetch unit that supports speculativebranching.The LPC1850/30/20/10 include up to 200 kB of on-chip SRAM data memory, a quad SPIFlash Interface (SPIFI), a State Configuration Timer (SCT) subsystem, two High-speedUSB controllers, Ethernet, LCD, an external memory controller, and multiple digital andanalog peripherals.
The LPC4350/30/20/10 are ARM Cortex-M4 based microcontrollers for embeddedapplications. The ARM Cortex-M4 is a next generation core that offers systemenhancements such as low power consumption, enhanced debug features, and a highlevel of support block integration.The LPC4350/30/20/10 operate at CPU frequencies of up to 150 MHz. The ARMCortex-M4 CPU incorporates a 3-stage pipeline, uses a Harvard architecture withseparate local instruction and data buses as well as a third bus for peripherals, andincludes an internal prefetch unit that supports speculative branching. The ARMCortex-M4 supports single-cycle digital signal processing and SIMD instructions. Ahardware floating-point processor is integrated in the core.The LPC4350/30/20/10 include an ARM Cortex-M0 coprocessor, up to 264 kB of datamemory, advanced configurable peripherals such as the State Configurable Timer (SCT)and the Serial General Purpose I/O (SGPIO) interface, two High-speed USB controllers,Ethernet, LCD, an external memory controller, and multiple digital and analog peripherals
This is the second half of our Transistor Circuits e-book. It contains a further 100 circuits, with many of them containing one or more Integrated Circuits (ICs).It's amazing what you can do with transistors but when Integrated Circuits came along, the whole field of electronics exploded.
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
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Xilinx UltraScale:The Next-Generation Architecture for Your Next-Generation Architecture
The Xilinx® UltraScale™ architecture delivers unprecedented levels of integration and capability with ASIC-class system- level performance for the most demanding applications.
The UltraScale architecture is the industr y's f irst application of leading-edge ASIC architectural enhancements in an All Programmable architecture that scales from 20 nm planar through 16 nm FinFET technologies and beyond, in addition to scaling from monolithic through 3D ICs. Through analytical co-optimization with the X ilinx V ivado® Design Suite, the UltraScale architecture provides massive routing capacity while intelligently resolving typical bottlenecks in ways never before possible. This design synergy achieves greater than 90% utilization with no performance degradation.
Some of the UltraScale architecture breakthroughs include:
• Strategic placement (virtually anywhere on the die) of ASIC-like system clocks, reducing clock skew by up to 50%
• Latency-producing pipelining is virtually unnecessary in systems with massively parallel bus architecture, increasing system speed and capability
• Potential timing-closure problems and interconnect bottlenecks are eliminated, even in systems requiring 90% or more resource utilization
• 3D IC integration makes it possible to build larger devices one process generation ahead of the current industr y standard
• Greatly increased system performance, including multi-gigabit serial transceivers, I/O, and memor y bandwidth is available within even smaller system power budgets
• Greatly enhanced DSP and packet handling
The Xilinx UltraScale architecture opens up whole new dimensions for designers of ultra-high-capacity solutions.
Abstract: Using a wafer-level package (WLP) can reduce the overall size and cost of your solution.However when using a WLP IC, the printed circuit board (PCB) layout can become more complex and, ifnot carefully planned, result in an unreliable design. This article presents some PCB designconsiderations and general recommendations for choosing a 0.4mm- or 0.5mm-pitch WLP for yourapplication.
