6.2.2 How IP Addresses are Used
The actual hardware connection via an Ethernet uses Ethernet adapter addresses (also
called MAC addresses). These are 48-bit addresses and are unique for every Ethernet
adapter manufactured. In order to send a packet to another computer, given the IP address
of the other computer, it is first determined if the packet needs to be sent directly to the
other computer or to the gateway. In either case, there is an Ethernet address on the local
network to which the packet must be sent. A table is maintained to allow the protocol
driver to determine the MAC address corresponding to a particular IP address. If the table
is empty, the MAC address is determined by sending an Ethernet broadcast packet to all
devices on the local network asking the device with the desired IP address to answer with
its MAC address. In this way, the table entry can be filled in. If no device answers, then
the device is nonexistent or inoperative, and the packet cannot be sent.
Some IP address ranges are reserved for use on internal networks, and can be allocated
freely as long as no two internal hosts have the same IP address. These internal IP
addresses are not routed to the Internet, and any internal hosts using one of these reserved
IP addresses cannot communicate on the external Internet without being connected to a
host that has a valid Internet IP address. The host would either translate the data, or it
would act as a proxy.
Each RCM3360/RCM3370 RabbitCore module has its own unique MAC address, which
consists of the prefix 0090C2 followed by a code that is unique to each RCM3360/
RCM3370 module. For example, a MAC address might be 0090C2C002C0.
TIP: You can always obtain the MAC address on your board by running the sample pro-
gram DISPLAY_MAC.C from the SAMPLES\TCPIP folder.
52
RabbitCore RCM3360/RCM3370
相关PDF资料
101-1050-BE-00025 ADPT USB 2 A FEMALE-2 5PIN .25M
10112627-101LF MINI-SAS HD 1X2 EXT PCB
10112628-101LF MINI-SAS HD 1X4 EXT PCB
10136-3000PC CONN MINI-D 36POS SOLDER PLUG
10136-6000EC CONN MDR PLUG 36POS IDC GOLD
10150-4CZ3PL CONN MDR PLUG 50POS VERT T/H
10150-72E2PC CONN MINI-D 50POS R/A PLUG
10150-8000EE CONN PLUG 50 POS MINI-D
相关代理商/技术参数
101-0955 功能描述:模块化系统 - SOM RCM2260 RABBITCORE MODULE RoHS:否 制造商:Digi International 外观尺寸:ConnectCore 9P 处理器类型:ARM926EJ-S 频率:150 MHz 存储容量:8 MB, 16 MB 存储类型:NOR Flash, SDRAM 接口类型:I2C, SPI, UART 工作电源电压:3.3 V 最大工作温度:+ 85 C 尺寸:1.97 in x 1.97 in x 6.1 in
101-0956 功能描述:开发板和工具包 - 其他处理器 Powercore Flex Kit US Version RoHS:否 制造商:Freescale Semiconductor 产品:Development Systems 工具用于评估:P3041 核心:e500mc 接口类型:I2C, SPI, USB 工作电源电压:
101-0957 功能描述:开发板和工具包 - 其他处理器 Powercore Flex Kit International Vers. RoHS:否 制造商:Freescale Semiconductor 产品:Development Systems 工具用于评估:P3041 核心:e500mc 接口类型:I2C, SPI, USB 工作电源电压:
101-0961 功能描述:模块化系统 - SOM RCM3720 CORE MOD. RoHS:否 制造商:Digi International 外观尺寸:ConnectCore 9P 处理器类型:ARM926EJ-S 频率:150 MHz 存储容量:8 MB, 16 MB 存储类型:NOR Flash, SDRAM 接口类型:I2C, SPI, UART 工作电源电压:3.3 V 最大工作温度:+ 85 C 尺寸:1.97 in x 1.97 in x 6.1 in
10-109611-3S 制造商:Amphenol Corporation 功能描述:10-109611-03S - Bulk
10-109611-4S 制造商:Amphenol Corporation 功能描述:10-109611-04S - Bulk
10-109614-02S 制造商:Amphenol Corporation 功能描述:ER 4C 4#16S SKT PLUG
10-109614-05P 制造商:Amphenol Industrial Operations 功能描述:ER 5C 5#16S PIN PLUG