GE冗余模块IC697CGR935GE冗余模块IC697CGR935GE冗余模块IC697CGR935-------------------------------------------------------------------------------------------------------------------以嵌入式微处理器和嵌入式操作系统为核心的嵌入式技术是近年来一项新兴的热门技术，特别是以ARM公司的32位IP核为基础的ARM嵌入式微处理器，以其高性能、低功耗、低成本等优势，得到了广泛的应用。然而，目前在网络存储领域，内商用市场上的网络存储系统大都采用x86等成熟的硬件平台和商业化操作系统，成本昂贵、核心技术知识产权受保护。本文提出把ARM9微处理器和源码开放的嵌入式Linux操作系统应用在网络存储领域，构建一个附网络存储NAS(NetworkattachedStorage)基本系统，拓展了ARM9微处理器的应用，也为NAS系统的发展提供了方向。NAS系统是一个具有专一功能的网络存储系统，可实现与网络设备直接连接，使客户机与存储器之间直接传送数据；结合具有开放式、强大和稳定的网络性能的嵌入式Linux操作系统，内置与网络连接所需的协议，能实现低成本、即插即用、管理和设置简单的存储系统。1系统结构NAS系统把存储设备和网络接口集成在一起，直接通过网络存取数据，使其成为专用的网络文件存储及文件备份设备。因此，一个基本的NAS系统应包括基本的硬件设备、接口，操作系统，网络通信和上层应用程序4个部分。在硬件方面，系统采用32位的嵌入式微处理器EP9315作为主CPU。由于EP9315集成1/10/100Mbps的以太网LAN控制器，因此只需外接物理层（PHY）接口芯片，即可实现稳定、高效率的以太网接入。在操作系统方面，作为一个只需要实现网络存储和文件管理的系统，应该采用面向存储的专用操作系统。基于Linux强大和稳定的网络功能、源代码的开放性，系统选用嵌入式Linux作为NAS的操作系统；通过对Linux的裁剪，去掉许多通用的功能，能大大提高设备的性能。网络通信方面：由于NAS服务器采用Linux操作系统，客户机PC一般都是Windows系统，Linux系统支持TCP/IP协议,但是不支持NetBIOS(NetworkBasicInputandOutputSystem)，因此两者之间的通信需要一个中介。本系统利用Samba来实现个功能。NAS系统设计框图在应用程序方面：NAS设备的远程访问和管理以及数据传输，都需要相应的应用程序来支持；否则，即使将NAS接入网络中，对用户来说它也只是个无法访问的“黑箱”。本系统的应用程序实现了硬盘管理、用户和组管理、网络配置、系统时间设置、网络共享管理等。NAS系统设计框图如图1所示。2系统硬件设技系统采用CirrusLogic公司的ARM9系列的32位微处理器EP9315作为主控制器。2.1EP9315主要特性介绍[2]EP9315内嵌先进的运行于200MHz的ARM920T微处理器内核，内核工作电压为1.8V，输入/输出电压为3.3V；内部集成了一个高性能的1/10/100Mbps以太网媒体访问控制器（MAC），通过与支持MII接口的外置PHY(物理层接口)简单连接，系统即可实现高性能、低开销的Internet访问功能。EP9315的IDE接口可以支持与两个ATAPI工业标准兼容设备的连接，支持主模式和从模式，其内部的DMA控制器支持MultiwordDMA和UltraDMA模式的数据传输。EP9315的其他特性还有：通用存储器接口（SDRAM、SRAM、ROM和Flash），Raster/LCD接口，带12位A/D转换器的触摸屏接口，键盘接口，UART接口，3通道USB2.0全速主口，12通道DMA控制器等。其丰富的外围接口大大降低了系统开发费用。2.2硬件电路P0900HSP0900HTP0900HUP0900HVP0900HXP0900HYP0900HZP0900JBP0900JCP0900JDP0900JEP0900JFP0900JGP0900JHP0900JJP0900JLP0900JMP0900JNP0900KAP0900KBP0900KCP0900KDP0900KEP0900KFP0900KGP0900KHP0900KJP0900KKP0900KLP0900KMP0900KNP0900LUP0900MAP0900MCP0900MDP0900MEP0900MFP0900MGP0900MHP0900MLP0900MMP0900MNP0900MPP0900MQP0900MRP0900MSP0900MTP0900MUP0900MVP0900MWP0900MXP0900NTP0900NVP0900NWP0900NXP0900NYP0900NZP0900PZP0900QAP0900QKP0900QLP0900RJP0900RKP0900RLP0900RMP0900RNP0900RUP0900RYP0900SAP0900SVP0900SWP0900SXP0900TBP0900TEP0900THP0900TLP0900TPP0900TQP0900TRP0900TSP0900UXP0900VNP0900WAP0900WFP0900WLP0900WSP0900WTP0900WUP0900WVP0900WWP0900ZAP0900ZBP0900ZRP0900ZSP0900ZUP0900ZVP0900ZWP0901AAP0901ABP0901ACP0901ADP0901AKP0901AXP0901AYP0901BJP0901BUP0901BXP0901BYP0901EDP0901EEP0901EFP0901EGP0901EHP0901EJP0901EKP0901ELP0901EMP0901ENP0901EPP0901ETP0901EUP0901EXP0901EYP0901EZP0901FAP0901FBP0901FCP0901FDP0901FJP0901FKP0901FLP0901FMP0901FNP0901FPP0901GEP0901GFP0901GGP0901GHP0901GJP0901HAP0901PEP0901PFP0901RRP0901SDP0901SEP0901VAP0901VJP0901VKP0901VLP0901VMP0901VNP0901VPP0901VQP0901VRP0901VTP0901XFP0901XTP0901XWP0901YJP0901YKP0901YRP0901YSP0901YTP0901YVP0902BLP0902BPP0902BQP0902BVP0902BWP0902BXP0902BYP0902CAP0902CBP0902CCP0902CDP0902CEP0902CFP0902DZP0902EAP0902EEP0902ESP0902HKP0902JDP0902JMP0902JNP0902KZP0902LNP0902LWP0902LXP0902LYP0902MFP0902MXP0902MYP0902NDP0902NXP0902NZP0902PHP0902QRP0902SFP0902SGP0902SHP0902SJP0902SKP0902SLP0902SMP0902SNP0902SPP0902UBP0902UCP0902UDP0902UEP0902UFP0902UGP0902UHP0902UJP0902UTP0902VGP0902VHP0902VJP0902VYP0902WDP0902WHP0902WTP0902WWP0902WXP0902WYP0902XAP0902XBP0902YTP0902YUP0902YVP0902YWP0902YXP0902YYP0902ZHP0902ZH-LP0902ZJP0902ZJ-LP0903AAP0903BXP0903CVP0903CWP0903EMP0903HLP0903NFP0903NKP0903PGP0903PHP0903PJP0903PQP0903QEP0903QFP0903QKP0903QQP0903QZP0903RLP0903SAP0903SBP0903SVP0903TWP0903UPP0903UQP0903URP0903USP0903UTP0903UUP0903UWP0903UXP0903UZP0903VSP0903VTP0903VVP0903VWP0903VYP0903WAP0903WBP0903WCP0903WDP0903WEP0903WFP0903WMP0903XKP0903XLP0903XRP0903XUP0903YEP0903ZEP0903ZLP0903ZMP0903ZNP0903ZPP0903ZQP0903ZRP0903ZWP0904AHP0904AJP0904AKP0904ALP0904ATP0904AUP0904BDP0904BEP0904BFP0904BHP0904BPP0904BQP0904BRP0904BSP0904BVP0904BWP0904FHP0904HAP0904HBP0904HLP0904HMP0904HNP0904HVP0904HWP0904HXP0911ACP0911AJP0911AKP0911ANP0911ATP0911AXP0911AYP0911AZP0911BAP0911BDP0911BEP0911BFP0911BGP0911BHP0911BJP0911BPP0911BQP0911BRP0911BSP0911BTP0911BUP0911BVP0911BWP0911BXP0911BYP0911BZP0911CAP0911CCP0911CDP0911CEP0911CFP0911CKP0911CLP0911CMP0911CNP0911CQP0911CTP0911CWP0911GJP0911GKP0911GLP0911GMP0911GNP0911GQP0911HDP0911HEP0911HTP0911JMP0911JNP0911JPP0911JQP0911JRP0911JSP0911JTP0911JUP0911JVP0911JWP0911JXP0911JYP0911KFP0911KGP0911KHP0911KJP0911KMP0911KNP0911KVP0911KWP0911LDP0911LGP0911LHP0911LMP0911LNP0911LPP0911LQP0911MLP0911NHP0911NJP0911NKP0911NLP0911NMP0911NNP0911NUP0911NVP0911NWP0911NX)