在車載自組網中,路由協議很大程度上決定了整個網絡的性能。如何有效的利用車流信息提高傳輸質量是改善路由性能的一個關鍵問題。本文基于速度-密度線性模型,提出了一種實時車流密度的路由協議RVDR(Real-time Vehicle Density Routing)。該協議通過與鄰居節(jié)點交換的速度信息,對相關道路車流密度進行預測,并給出基于車流密度信息的路徑選擇方法。仿真結果表明,與現有協議相比,RVDR協議在實時性和高效性等性能方面得到改進。
為提升虛擬儀器傳輸速率與實時性能,擴展監(jiān)測范圍,在VC的軟件平臺上設計了一種全功能虛擬示波器。與傳統虛擬示波器相比,該系統采用嵌入式系統完成信號采集,采用工業(yè)以太網為傳輸介質,通過線性插值算法和多線程編程思想,實現波形顯示、參數計算、頻譜分析以及波形存儲及回放功能。實驗結果表明,該虛擬示波器可以實現20 kHz采樣頻率下的波形精確顯示,達到預期的各項指標。
Abstract:
o enhance the transfer rate and real-time of virtual instrument performance, expand scope of monitoring, this paper uses the VCs software platform to design a fully functional virtual oscilloscope. Compared with traditional virtual oscilloscope, this system adopts the embedded system to complete the data acquisition, industrial Ethernet as the transmission medium used by the linear interpolation algorithm and multi-threaded programming ideas, namely to achieve waveform display, parameter calculation, spectrum analysis and waveform storage and playback. Experimental results show that the virtual oscilloscope can accurately display the waveform with 20kHz sampling frequency, and achieve the desired targets.
The use of the Wind River VxWorks Real-Time Operating System (RTOS) on Virtex™-4embedded PowerPC™ processors continues to be a popular choice for high performanceFPGA designs. The introduction of the Wind River Workbench design environment has enableda new and easier way for designers to control the configuration of the VxWorks kernel. Thisguide shows the steps required to build and configure a ML403 Embedded DevelopmentPlatform to boot and run the VxWorks RTOS. A VxWorks bootloader is created, programmedinto Flash, and used to boot the design. The concepts presented here can be scaled to anyPowerPC enabled development platform.
The LPC2292/2294 microcontrollers are based on a 16/32-bit ARM7TDMI-S CPU with real-time emulation and embedded trace support, together with 256 kB of embedded high-speed flash memory. A 128-bit wide memory interface and a unique accelerator architecture enable 32-bit code execution at the maximum clock rate. For critical code size applications, the alternative 16-bit Thumb mode reduces code by more than 30 pct with minimal performance penalty.
With their 144-pin package, low power consumption, various 32-bit timers, 8-channel 10-bit ADC, 2/4 (LPC2294) advanced CAN channels, PWM channels and up to nine external interrupt pins these microcontrollers are particularly suitable for automotive and industrial control applications as well as medical systems and fault-tolerant maintenance buses. The number of available fast GPIOs ranges from 76 (with external memory) through 112 (single-chip). With a wide range of additional serial communications interfaces, they are also suited for communication gateways and protocol converters as well as many other general-purpose applications.
Remark: Throughout the data sheet, the term LPC2292/2294 will apply to devices with and without the /00 or /01 suffix. The suffixes /00 and /01 will be used to differentiate from other devices only when necessary.
Abstract: This article discusses the benefits of a G3-PLC-based automation system and presents a real-world example of a systemfor reducing energy usage and lowering maintenance costs in tunnels. The basic system design is explained and key performance
The NXP LPC315x combine an 180 MHz ARM926EJ-S CPU core, High-speed USB 2.0OTG, 192 KB SRAM, NAND flash controller, flexible external bus interface, an integratedaudio codec, Li-ion charger, Real-Time Clock (RTC), and a myriad of serial and parallelinterfaces in a single chip targeted at consumer, industrial, medical, and communicationmarkets. To optimize system power consumption, the LPC315x have multiple powerdomains and a very flexible Clock Generation Unit (CGU) that provides dynamic clockgating and scaling.The LPC315x is implemented as multi-chip module with two side-by-side dies, one fordigital fuctions and one for analog functions, which include a Power Supply Unit (PSU),audio codec, RTC, and Li-ion battery charger.
Abstract: This application note explains how to design an intelligent lighting controller that senses and measures the ambient lightlevel with an ambient light sensor (ALS). Equipped with a real-time clock (RTC), the controller also knows when to turn lighting on oroff at specified times. The system presented in this document can be used to control all luminaires that are mains-supply operated.Controller software is also provided in hex format.