在研究傳統(tǒng)家用燃?xì)鈭?bào)警器的基礎(chǔ)上，以ZigBee協(xié)議為平臺(tái)，構(gòu)建mesh網(wǎng)狀網(wǎng)絡(luò)實(shí)現(xiàn)網(wǎng)絡(luò)化的智能語(yǔ)音報(bào)警系統(tǒng)。由于傳感器本身的溫度和實(shí)際環(huán)境溫度的影響，傳感器標(biāo)定后采用軟件補(bǔ)償方法。為了減少系統(tǒng)費(fèi)用，前端節(jié)點(diǎn)采用半功能節(jié)點(diǎn)設(shè)備，路由器和協(xié)調(diào)器采用全功能節(jié)點(diǎn)設(shè)備，構(gòu)建mesh網(wǎng)絡(luò)所形成的家庭內(nèi)部報(bào)警系統(tǒng)，通過(guò)通用的電話接口連接到外部的公用電話網(wǎng)絡(luò)，啟動(dòng)語(yǔ)音模塊進(jìn)行報(bào)警。實(shí)驗(yàn)結(jié)果表明，在2.4 GHz頻率下傳輸，有墻等障礙物的情況下，節(jié)點(diǎn)的傳輸距離大約為35 m，能夠滿足家庭需要，且系統(tǒng)工作穩(wěn)定，但在功耗方面仍需進(jìn)一步改善。
Abstract:
On the basis of studying traditional household gas alarm system, this paper proposed the platform for the ZigBee protocol，and constructed mesh network to achieve network-based intelligent voice alarm system. Because of the sensor temperature and the actual environment temperature, this system design used software compensation after calibrating sensor. In order to reduce system cost, semi-functional node devices were used as front-end node, however, full-function devices were used as routers and coordinator，constructed alarm system within the family by building mesh network，connected to the external public telephone network through the common telephone interface, started the voice alarm module. The results indicate that nodes transmit about 35m in the distance in case of walls and other obstacles by 2.4GHz frequency transmission, this is able to meet family needs and work steadily, but still needs further improvement in power consumption.
為了能夠滿足基站易于選址、優(yōu)質(zhì)快速的建站要求和易維護(hù)、低成本、高可靠的運(yùn)行要求，本文對(duì)以方艙來(lái)實(shí)現(xiàn)一體化結(jié)構(gòu)基站做出一番探討。從系統(tǒng)設(shè)計(jì)的觀點(diǎn)闡述了移動(dòng)通信高性能基站天線設(shè)計(jì)的幾個(gè)關(guān)鍵問(wèn)題，介紹了智能天線技術(shù)在基站中的應(yīng)用，并且用HFSS軟件仿真了一種新型的對(duì)稱陣子天線，該天線駐波比小于2的帶寬可以達(dá)到60%，具有良好的寬頻帶特性。
Abstract:
In order to meet the station construction requirement of easy site selection and fast base station， and meet the operational requirement of easy maintenance， low cost and high reliability， this paper discussed the unified architecture base station using shelter. Several key problems of high performance mobile communication base station antenna were illustrated from the view of system design， the application of smart antenna in base station was also introduced. And a novel dipole antenna was simulated by using HFSS， the VSWR of the antenna is less than 2， and the bandwidth was reach to 60%. So it has good broadband properties.
通過(guò)以太網(wǎng)遠(yuǎn)程配置Nios II 處理器 應(yīng)用筆記
Firmware in embedded hardware systems is frequently updated over the Ethernet. For
embedded systems that comprise a discrete microprocessor and the devices it controls, the
firmware is the software image run by the microprocessor. When the embedded system
includes an FPGA, firmware updates include updates of the hardware image on the FPGA. If
the FPGA includes a Nios® II soft processor, you can upgrade both the Nios II processor—as
part of the FPGA image—and the software that the Nios II processor runs, in a single remote
configuration session.
Field Programmable Gate Arrays (FPGAs) are becoming a critical part of every system design. Many vendors offer many different architectures and processes. Which one is right for your design? How do you design one of these so that it works correctly and functions as you expect in your entire system? These are the questions that this paper sets out to answer.
The purpose of this application note is to describe the main elements of
an RS-422 and RS-485 system. This application note attempts to cover
enough technical details so that the system designer will have considered all
the important aspects in his data system design. Since both RS-422 and RS-
485 are data transmission systems that use balanced differential signals, it is
appropriate to discuss both systems in the same application note. Throughout
this application note the generic terms of RS-422 and RS-485 will be used to
represent the EIA/TIA-422 and EIA/TIA-485 Standards.
我們做微機(jī)硬件綜合實(shí)驗(yàn)做的一個(gè)交通信號(hào)燈實(shí)時(shí)控制系統(tǒng)設(shè)計(jì)，很好哦！還附有實(shí)驗(yàn)報(bào)告．-A traffic lights real-time control system design of the micro computer hardware experiment.PS:contain the experiment report
TinyLogin is a suite of tiny Unix utilities for handling logging into,
being authenticated by, changing one s password for, and otherwise
maintaining users and groups on an embedded system. It also provides
shadow password support to enhance system security. TinyLogin is, as the
name implies, very small, and makes an excellent complement to BusyBox
on an embedded System. It can be used without BusyBox, of course, but I
envision them being used together most of the time.
