The AT89C52 is a low-power, high-performance CMOS 8-bit microcomputer with 8Kbytes of Flash programmable and erasable read only memory (PEROM). The deviceis manufactured using Atmel’s high-density nonvolatile memory technology and iscompatible with the industry-standard 80C51 and 80C52 instruction set and pinout.The on-chip Flash allows the program memory to be reprogrammed in-system or by aconventional nonvolatile memory programmer. By combining a versatile 8-bit CPUwith Flash on a monolithic chip, the Atmel AT89C52 is a powerful microcomputerwhich provides a highly-flexible and cost-effective solution to many embedded controlapplications.
HDB3(High Density Bipolar三階高密度雙極性)碼是在AMI碼的基礎(chǔ)上改進(jìn)的一種雙極性歸零碼,它除具有AMI碼功率譜中無直流分量,可進(jìn)行差錯(cuò)自檢等優(yōu)點(diǎn)外,還克服了AMI碼當(dāng)信息中出現(xiàn)連“0”碼時(shí)定時(shí)提取困難的缺點(diǎn),而且HDB3碼頻譜能量主要集中在基波頻率以下,占用頻帶較窄,是ITU-TG.703推薦的PCM基群、二次群和三次群的數(shù)字傳輸接口碼型,因此HDB3碼的編解碼就顯得極為重要了[1]。目前,HDB3碼主要由專用集成電路及相應(yīng)匹配的外圍中小規(guī)模集成芯片來實(shí)現(xiàn),但集成程度不高,特別是位同步提取非常復(fù)雜,不易實(shí)現(xiàn)。隨著可編程器件的發(fā)展,這一難題得到了很好地解決。
Designing withProgrammable Logicin an Analog WorldProgrammable logic devicesrevolutionized digital design over 25years ago, promising designers a blankchip to design literally any functionand program it in the field. PLDs canbe low-logic density devices that usenonvolatile sea-of-gates cells calledcomplex programmable logic devices(CPLDs) or they can be high-densitydevices based on SRAM look-up tables
Designing withProgrammable Logicin an Analog WorldProgrammable logic devices revolutionizeddigital design over 25 years ago,promising designers a blank chip todesign literally any function and programit in the field. PLDs can be low-logicdensity devices that use nonvolatilesea-of-gates cells called complexprogrammable logic devices (CPLDs)or they can be high-density devicesbased on SRAM look-up tables (LUTs)
在車載自組網(wǎng)中,路由協(xié)議很大程度上決定了整個(gè)網(wǎng)絡(luò)的性能。如何有效的利用車流信息提高傳輸質(zhì)量是改善路由性能的一個(gè)關(guān)鍵問題。本文基于速度-密度線性模型,提出了一種實(shí)時(shí)車流密度的路由協(xié)議RVDR(Real-time Vehicle Density Routing)。該協(xié)議通過與鄰居節(jié)點(diǎn)交換的速度信息,對(duì)相關(guān)道路車流密度進(jìn)行預(yù)測,并給出基于車流密度信息的路徑選擇方法。仿真結(jié)果表明,與現(xiàn)有協(xié)議相比,RVDR協(xié)議在實(shí)時(shí)性和高效性等性能方面得到改進(jìn)。
HDB3(High Density Bipolar三階高密度雙極性)碼是在AMI碼的基礎(chǔ)上改進(jìn)的一種雙極性歸零碼,它除具有AMI碼功率譜中無直流分量,可進(jìn)行差錯(cuò)自檢等優(yōu)點(diǎn)外,還克服了AMI碼當(dāng)信息中出現(xiàn)連“0”碼時(shí)定時(shí)提取困難的缺點(diǎn),而且HDB3碼頻譜能量主要集中在基波頻率以下,占用頻帶較窄,是ITU-TG.703推薦的PCM基群、二次群和三次群的數(shù)字傳輸接口碼型,因此HDB3碼的編解碼就顯得極為重要了[1]。目前,HDB3碼主要由專用集成電路及相應(yīng)匹配的外圍中小規(guī)模集成芯片來實(shí)現(xiàn),但集成程度不高,特別是位同步提取非常復(fù)雜,不易實(shí)現(xiàn)。隨著可編程器件的發(fā)展,這一難題得到了很好地解決。
Designing withProgrammable Logicin an Analog WorldProgrammable logic devices revolutionizeddigital design over 25 years ago,promising designers a blank chip todesign literally any function and programit in the field. PLDs can be low-logicdensity devices that use nonvolatilesea-of-gates cells called complexprogrammable logic devices (CPLDs)or they can be high-density devicesbased on SRAM look-up tables (LUTs)
Designing withProgrammable Logicin an Analog WorldProgrammable logic devicesrevolutionized digital design over 25years ago, promising designers a blankchip to design literally any functionand program it in the field. PLDs canbe low-logic density devices that usenonvolatile sea-of-gates cells calledcomplex programmable logic devices(CPLDs) or they can be high-densitydevices based on SRAM look-up tables