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Rabbit Semiconductor RCM3200 - ...t communications and the Internet protocols the
device uses. Or you can save a lot of time by starting with a module that
contains a CPU, Ethern...
Dallas Semiconductor DSTINIm400 - ... a wholly owned subsidiary of Maxim Integrated Products.
Hardware. TINI stands for Tiny InterNet Interface. Technically, the TINI
isn’t a ...
The MCF5282 supports a subset of the Motorola 68000 - ...00 microcontroller from aJile Systems
Inc. The aJ-100’s native execution of Java bytecodes results in very fast performance. The chip is base...
Ubicom IP2022 Wireless Network Processor - ...y to add networking capability. This section describes a selection of products.
Lantronix Device Server
At a glance: enables any device with an ...
EDTP Electronics Packet Whacker - ... Ethernet interface only. The circuit board contains a Realtek RTL8019AS
Ethernet controller, an RJ-45 connector, two headers that bring out the si...
NE2000 Compatibility - ...E2000-compatible code.
A major feature of the ’8390 is its set of internal registers. By reading and
writing to the registers, a CPU can c...
Using the Internet Protocol in Local and Internet Communications - ... travel on the Internet must use IP. And because TCP and
UDP are designed to work along with IP, local communications that use
TCP or UDP also use...
There are several options for obtaining an Internet connection - ...ossible. Table 4-1 compares the
capabilities of the different methods. Not every connection type is available
in all locations.
Depending on ...
Every computer that communicates over the Internet must have an IP address - ...typically changes only occasionally).
An embedded system may store a static IP address in non-volatile memory,
either within an application...
Obtaining and Using a Domain Name - ...dress. For example, to view a
server’s home page, in the Address text box of a Web browser, you enter
http:// followed by the server&rsquo...
Inside the Internet Protocol - ... section introduces IP, including how computers obtain IP addresses,
the format of IP datagrams, how IP and the domain name system help in
getti...
A computer that uses the Internet Protocol must have an IP address - ...to express an IP address is in dotted-quad format, such as
192.168.111.1.
Assigning Addresses
Each IP datagram includes t...
With classless addressing the network address and IP prefix - ...s 192.0.2 (three bytes, or 24 bits), and the final eight bits in the IP
address are the host address.
In routing datagrams for addresses that us...
Considerations when Using Dynamic IP Addresses - ...ns a permanent, or static,
address to every computer that connects, it will eventually run out of
addresses, even if only a few customers connec...
Hosts that support IP must also support the ICMP - ... routers.
ICMP messages travel in IP datagrams. The Protocol field in the IP header
is 1 to indicate ICMP. The first byte in the data portion of...
UDP provides the basics for transferring data - ...equence numbers, a destination can
place received messages in the order they were sent, even if they were
received out of order. Sequence number...
A TCP connection has two endpoints - ...ns to a number of remote
computers at the same time. A pair of computers can have multiple connections
to each other at the same time, as long a...
Serving Web Pages with Dynamic Data - ...
A Web browser such as Microsoft’s Internet Explorer is a client application
that uses HTTP to request Web pages from servers on the Intern...
To serve its Web page the Rabbit module uses HTTP functions - ...e the browser how to display the page’s contents. Each
tag consists of text enclosed by angle brackets ( ). The In Depth section of
this n...
The FTP defines a standard protocol for transferring files - ... A client initiates
communications with a server and sends requests to transmit or
receive files. In most cases, an embedded system that needs t...
All computer networks have some things in common - ...d and receive information of any kind, over distances large and
small, via wires or through the air. Computers of different types can communicate
...
Make designing and maintaining a network as easy as possible - ...ules
don’t need to know details about how the other modules accomplish
their tasks.
The modular approach has a couple of benefits. If e...
IP Internet Addressing and Routing - ...P also use IP.
The term TCP/IP refers to communications that use TCP and IP. The term
can also refer more broadly to the suite of protocols that...
Requirements for Internet Communications - ...ting with an Internet
Service Provider (ISP). The ISP provides an IP address that identifies the
computer on the Internet.
Domain names such ...
With Ethernet the hardware manages the network traffic - ...ller waits for the network to be idle and then
attempts to transmit. If two or more interfaces try to transmit at the same
time, the interfaces ...
Ethernet isn not very efficient when transferring small amounts of data - ...rame that contains the
byte must also include 26 bytes of overhead plus 45 bytes of padding. Other
protocols such as TCP and IP add more overhea...
All data in an Ethernet network travels in structures called frames - ...g, and extracts and stores the information in received frames.
Table 1-1 shows the fields in an IEEE 802.3 Ethernet frame. The fields add
synchr...
In Ethernet networks that use half duplex interfaces - ...rol. In some networks,
one computer is the master, and the other computers transmit only after
receiving permission from the master. The USB int...
An Ethernet interface can be half duplex or full duplex - ...cause there are no collisions to detect.
With two data paths available, a full-duplex segment can theoretically support
twice the traffic of a h...
Putting together an Ethernet network - ...r system’s speed and
cabling are compatible with the network.
In developing a networked embedded system, it’s likely that you’...
A network interface can not do much without a connection - ...ows the use of three cable types: twisted-pair,
fiber-optic, and coaxial cable.
Twisted-pair cable is popular because it’s inexpensiv...
Networks of all three speeds can use cable - ...
Cable Categories
Networks of all three speeds can use cable that meets the Category 5e specification
defined in EIA/TIA-568-B. A C...
There are two common pinouts for the RJ 45 connectors - ...wires in pairs 2 and 3. Within a cable (except for crossover cables), both ends must use the same pinout. The only difference between the two pinouts ...
Fiber optic cables do not use electrical current - ...of infrared energy. Fiber-optic communications
may use visible or infrared light.
As with twisted-pair networks, fiber-optic networks use repeat...
Specifications for fiber optic cable - ...de fiber has
just one path and can carry signals at high bit rates and over long distances.
In multimode fiber, a signal may use any of multiple...
To reduce problems caused by electromagnetic interference - ...
being transmitted. But some embedded systems must function where the
components are subjected to one or more of the following:
• E...
Connect ethernet interface to a wireless network - ...andard, like Ethernet’s 802.3
standard, specifies a physical layer and a method of media-access control for
networking. The physical layer...
The different media systems use different encoding methods - ...t level for the second half of the
bit period. A logic 0 is the reverse: the signal is high for the first half of the
bit period and low for the...
Ethernet cable segments have maximum permitted lengths - ... a repeater hub also detects and responds
to collisions and prevents traffic from misbehaving interfaces from reaching
the other interfaces in t...
latest articles under "Ethernet"
Navigation: Categories » Computers and technology » Ethernet
Below is a list of all Ethernet articles. If you want to find a tutorial by keywords, all you have to do is a quick search in our directory. Just use the search option available at the top-right side of the page. The website search is powered by web-articles. Or, if you want to read specific Ethernet tutorial, just point to it. The newest articles and tutorials are shown first in the list. To access the last ones, browse the pages 2, 3, 4... at the bottom. Also, you may browse articles alphabetically ordered.
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Below is a list of all Ethernet articles. If you want to find a tutorial by keywords, all you have to do is a quick search in our directory. Just use the search option available at the top-right side of the page. The website search is powered by web-articles. Or, if you want to read specific Ethernet tutorial, just point to it. The newest articles and tutorials are shown first in the list. To access the last ones, browse the pages 2, 3, 4... at the bottom. Also, you may browse articles alphabetically ordered.
Page# 1 (last added articles shown first)
Rabbit Semiconductor RCM3200 (12/06/2007)
(...) Selecting Components As with any project, familiarity can make a big difference in how easy it is to get something up and running. On the software side, both C and Java are popular languages for programming networked embedded systems. If you have experience in one of these languages, it makes sense to stick with it. (...)
(...) Selecting Components As with any project, familiarity can make a big difference in how easy it is to get something up and running. On the software side, both C and Java are popular languages for programming networked embedded systems. If you have experience in one of these languages, it makes sense to stick with it. (...)
Dallas Semiconductor DSTINIm400 (12/06/2007)
(...) The DSTINIm400 Networked Microcontroller Evaluation Kit (Network article 3-4) is a module that implements the TINI platform. The module’s circuit board contains a Dallas Semiconductor DS80C400 Network Microcontroller, which is a much enhanced, high-speed derivative of Intel Corporation’s long-popular 8051 microcontroller. The high speed comes from a fast clock and the ability to execute instructions in fewer clock cycles than an 8051. (...)
(...) The DSTINIm400 Networked Microcontroller Evaluation Kit (Network article 3-4) is a module that implements the TINI platform. The module’s circuit board contains a Dallas Semiconductor DS80C400 Network Microcontroller, which is a much enhanced, high-speed derivative of Intel Corporation’s long-popular 8051 microcontroller. The high speed comes from a fast clock and the ability to execute instructions in fewer clock cycles than an 8051. (...)
The MCF5282 supports a subset of the Motorola 68000 (12/06/2007)
(...) The chip is based on the JEM processor developed at Rockwell Collins. The JStik adds a high-speed I/O bus that can operate at bursts of 50 Megabytes per second, two RS-232 ports, and SPI and I2C interfaces. The board fits into a 60-contact SIMM socket and has an RJ-45 plug and additional I/O connectors. (...)
(...) The chip is based on the JEM processor developed at Rockwell Collins. The JStik adds a high-speed I/O bus that can operate at bursts of 50 Megabytes per second, two RS-232 ports, and SPI and I2C interfaces. The board fits into a 60-contact SIMM socket and has an RJ-45 plug and additional I/O connectors. (...)
Ubicom IP2022 Wireless Network Processor (12/06/2007)
(...) lantronix.com) Hardware: Lantronix offers its Device Servers in a variety of packages, including devices in enclosures, circuit boards and chips for incorporating into other devices, and a server squeezed into a slightly extended RJ-45 connector. Each server has a TTL-compatible asynchronous serial port for communicating with an external device or system and an RJ-45 connector for connecting to an Ethernet network. (...)
(...) lantronix.com) Hardware: Lantronix offers its Device Servers in a variety of packages, including devices in enclosures, circuit boards and chips for incorporating into other devices, and a server squeezed into a slightly extended RJ-45 connector. Each server has a TTL-compatible asynchronous serial port for communicating with an external device or system and an RJ-45 connector for connecting to an Ethernet network. (...)
EDTP Electronics Packet Whacker (12/06/2007)
(...) The Whacked 8051 Development Board includes Packet Whacker circuits and adds a Philips P89C668 8051-compatible microcontroller and 64 kilobytes of Flash memory. Software. EDTP provides example Packet Whacker firmware for UDP and TCP communications using a Microchip PIC16F877. (...)
(...) The Whacked 8051 Development Board includes Packet Whacker circuits and adds a Philips P89C668 8051-compatible microcontroller and 64 kilobytes of Flash memory. Software. EDTP provides example Packet Whacker firmware for UDP and TCP communications using a Microchip PIC16F877. (...)
NE2000 Compatibility (12/06/2007)
(...) Offsets 01h through 0Fh on each page store additional register values. On power-up or reset, program code typically initializes the registers to desired values before Ethernet data transfers begin. An NE2000-compatible chip should support all of the ’8390’s registers. (...)
(...) Offsets 01h through 0Fh on each page store additional register values. On power-up or reset, program code typically initializes the registers to desired values before Ethernet data transfers begin. An NE2000-compatible chip should support all of the ’8390’s registers. (...)
Using the Internet Protocol in Local and Internet Communications (12/06/2007)
(...) An Internet Service Provider (ISP) can provide one or more IP addresses and a connection to a router that can communicate over the Internet. Customers use a variety of ways to connect to ISPs. A high-volume user, including the networks at some large businesses, government offices, and schools, may have a dedicated, high-speed connection to an ISP. (...)
(...) An Internet Service Provider (ISP) can provide one or more IP addresses and a connection to a router that can communicate over the Internet. Customers use a variety of ways to connect to ISPs. A high-volume user, including the networks at some large businesses, government offices, and schools, may have a dedicated, high-speed connection to an ISP. (...)
There are several options for obtaining an Internet connection (12/06/2007)
(...) Most microcontrollers have an on-chip UART and require only a TTL-to-RS-232 converter. A computer that connects to the Internet via an RS-232 connection to a modem doesn’t have to support Ethernet at all. Instead, the computer can use the Point-to-Point Protocol (PPP) to send and receive IP datagrams over the RS-232 connection. (...)
(...) Most microcontrollers have an on-chip UART and require only a TTL-to-RS-232 converter. A computer that connects to the Internet via an RS-232 connection to a modem doesn’t have to support Ethernet at all. Instead, the computer can use the Point-to-Point Protocol (PPP) to send and receive IP datagrams over the RS-232 connection. (...)
Every computer that communicates over the Internet must have an IP address (12/06/2007)
(...) If you have a local network with multiple computers that need Internet access, it’s often easier, more secure, and less expensive to have all of the computers share a single public IP address for Internet communications. Some ISPs charge for each connected computer whether or not they share an IP address, however. Two ways to enable multiple computers to share a public IP address are with a router that supports the Network Address Translation (NAT) protocol and with a Windows PC configured as an Internet Connection Sharing host. (...)
(...) If you have a local network with multiple computers that need Internet access, it’s often easier, more secure, and less expensive to have all of the computers share a single public IP address for Internet communications. Some ISPs charge for each connected computer whether or not they share an IP address, however. Two ways to enable multiple computers to share a public IP address are with a router that supports the Network Address Translation (NAT) protocol and with a Windows PC configured as an Internet Connection Sharing host. (...)
Obtaining and Using a Domain Name (12/06/2007)
(...) com or dalsemi.com. Another advantage of a domain name is that it can remain constant. (...)
(...) com or dalsemi.com. Another advantage of a domain name is that it can remain constant. (...)
Inside the Internet Protocol (12/06/2007)
(...) The router examines the destination’s IP address and uses the address in deciding where to forward the datagram. At the destination computer, the Ethernet layer or another network interface passes the IP datagram to the IP layer, which removes the IP header. Information in the header tells the computer what protocol layer, such as TCP or UDP, should receive the datagram’s message. (...)
(...) The router examines the destination’s IP address and uses the address in deciding where to forward the datagram. At the destination computer, the Ethernet layer or another network interface passes the IP datagram to the IP layer, which removes the IP header. Information in the header tells the computer what protocol layer, such as TCP or UDP, should receive the datagram’s message. (...)
A computer that uses the Internet Protocol must have an IP address (12/06/2007)
(...) In a local network with no direct connection to other networks, the address only needs to be different from the other addresses in the local network. In theory an isolated local network could use any IP addresses, but the IP standard reserves three blocks of addresses for local use. For communicating over the Internet, the address must be different from the address of every other computer on the Internet. (...)
(...) In a local network with no direct connection to other networks, the address only needs to be different from the other addresses in the local network. In theory an isolated local network could use any IP addresses, but the IP standard reserves three blocks of addresses for local use. For communicating over the Internet, the address must be different from the address of every other computer on the Internet. (...)
With classless addressing the network address and IP prefix (12/06/2007)
(...) 2.0/24, the network address is 192.0. (...)
(...) 2.0/24, the network address is 192.0. (...)
Considerations when Using Dynamic IP Addresses (12/06/2007)
(...) A client may request an infinite lease or suggest a lease time, but servers aren’t required to comply with these requests. The lease time is a 32-bit value in seconds, with FFFFFFFFh indicating an infinite lease. On receiving a request for an IP address, a DHCP server uses the previously assigned address for that host if available. (...)
(...) A client may request an infinite lease or suggest a lease time, but servers aren’t required to comply with these requests. The lease time is a 32-bit value in seconds, with FFFFFFFFh indicating an infinite lease. On receiving a request for an IP address, a DHCP server uses the previously assigned address for that host if available. (...)
Hosts that support IP must also support the ICMP (12/06/2007)
(...) Also included is a review of options for obtaining code to support UDP, TCP, and IP in embedded systems. The Ethernet standard specifies a way to transfer information between computers in a local network. But Ethernet alone doesn’t provide some things that many data transfers require. (...)
(...) Also included is a review of options for obtaining code to support UDP, TCP, and IP in embedded systems. The Ethernet standard specifies a way to transfer information between computers in a local network. But Ethernet alone doesn’t provide some things that many data transfers require. (...)
UDP provides the basics for transferring data (12/06/2007)
(...) TCP is a called a connection-oriented protocol because processes can’t exchange data until they have exchanged communications to establish a connection with each other. TCP is called a reliable protocol because the handshaking, checksum, and sequence and acknowledge numbers enable the source to verify that data has arrived at its destination without error. A TCP segment consists of a header optionally followed by a data payload. (...)
(...) TCP is a called a connection-oriented protocol because processes can’t exchange data until they have exchanged communications to establish a connection with each other. TCP is called a reliable protocol because the handshaking, checksum, and sequence and acknowledge numbers enable the source to verify that data has arrived at its destination without error. A TCP segment consists of a header optionally followed by a data payload. (...)
A TCP connection has two endpoints (12/06/2007)
(...) Network article 5-3 shows typical communications in a handshake between two processes, the client and server, using the following communications: 1. The client initiates the handshake by sending a segment containing an initial sequence number. In the example, the sequence number is 100. (...)
(...) Network article 5-3 shows typical communications in a handshake between two processes, the client and server, using the following communications: 1. The client initiates the handshake by sending a segment containing an initial sequence number. In the example, the sequence number is 100. (...)
Serving Web Pages with Dynamic Data (12/06/2007)
(...) This networking tutorial focuses on Web servers. With an Internet connection, a Web server can serve pages to any browser on the Internet. Or a server may be programmed to respond to requests only from specific IP addresses. (...)
(...) This networking tutorial focuses on Web servers. With an Internet connection, a Web server can serve pages to any browser on the Internet. Or a server may be programmed to respond to requests only from specific IP addresses. (...)
To serve its Web page the Rabbit module uses HTTP functions (12/06/2007)
(...) Each of the four lines that follow contains a Server Side Include #echo directive that inserts the value of a variable on the page. A Server Side Include directive uses the same delimiters as an HTML comment. A comment, which is text that the browser ignores and doesn’t display, is enclosed by <!-- and -->. (...)
(...) Each of the four lines that follow contains a Server Side Include #echo directive that inserts the value of a variable on the page. A Server Side Include directive uses the same delimiters as an HTML comment. A comment, which is text that the browser ignores and doesn’t display, is enclosed by <!-- and -->. (...)
The FTP defines a standard protocol for transferring files (12/06/2007)
(...) Files are of course useful in desktop computers, where you select files to run programs, view documents and images, and perform other tasks. Embedded systems can support file systems as well. A small embedded system may just store data in specified locations in memory, with no need to place the data in named files. (...)
(...) Files are of course useful in desktop computers, where you select files to run programs, view documents and images, and perform other tasks. Embedded systems can support file systems as well. A small embedded system may just store data in specified locations in memory, with no need to place the data in named files. (...)
All computer networks have some things in common (12/06/2007)
(...) Many products designed for use in networks have support for Ethernet built in. A router, or gateway, enables an Ethernet network to communicate with computers in other networks, including computers on the Internet. Two or more computers that share a network connection form a local area network, or LAN. (...)
(...) Many products designed for use in networks have support for Ethernet built in. A router, or gateway, enables an Ethernet network to communicate with computers in other networks, including computers on the Internet. Two or more computers that share a network connection form a local area network, or LAN. (...)
Make designing and maintaining a network as easy as possible (12/06/2007)
(...) In an embedded system, the program code may be referred to as firmware, which typically means that the code is stored in Flash memory or another nonvolatile memory chip, rather than on a disk drive. In general, with software stored on a drive, users can install, run, and uninstall applications as needed. In contrast, firmware tends to be an integral, seldom-changing part of the device. (...)
(...) In an embedded system, the program code may be referred to as firmware, which typically means that the code is stored in Flash memory or another nonvolatile memory chip, rather than on a disk drive. In general, with software stored on a drive, users can install, run, and uninstall applications as needed. In contrast, firmware tends to be an integral, seldom-changing part of the device. (...)
IP Internet Addressing and Routing (12/06/2007)
(...) The IP layer encapsulates the TCP segment in an IP datagram, which consists of a header followed by a data portion that may contain a UDP datagram or a TCP segment (Network article 1-3). The header has fields for the source and destination IP addresses, error checking of the header, routing, and a value that identifies the protocol, such as TCP or UDP, used by the data portion. In a similar way, a UDP layer may pass a UDP datagram to the IP layer. (...)
(...) The IP layer encapsulates the TCP segment in an IP datagram, which consists of a header followed by a data portion that may contain a UDP datagram or a TCP segment (Network article 1-3). The header has fields for the source and destination IP addresses, error checking of the header, routing, and a value that identifies the protocol, such as TCP or UDP, used by the data portion. In a similar way, a UDP layer may pass a UDP datagram to the IP layer. (...)
Requirements for Internet Communications (12/06/2007)
(...) Domain names are available from a variety of registrars for a yearly fee. Local networks that connect to the Internet typically have a firewall, which is hardware, software, or a combination that protects the local network by limiting the types of communications that local computers can send and receive. To make a server or other resource available on the Internet, you may need to configure your firewall to permit receiving requests or other communications from outside the local network. (...)
(...) Domain names are available from a variety of registrars for a yearly fee. Local networks that connect to the Internet typically have a firewall, which is hardware, software, or a combination that protects the local network by limiting the types of communications that local computers can send and receive. To make a server or other resource available on the Internet, you may need to configure your firewall to permit receiving requests or other communications from outside the local network. (...)
With Ethernet the hardware manages the network traffic (12/06/2007)
(...) It Can Span Long Distances A single twisted-pair cable between two computers or between a repeater hub or switch and a computer can be 100 meters. A half-duplex segment of fiber-optic cable in a 10-Mb/s system can be as long as 2000 meters, while a full-duplex segment can be as long as 5 kilometers. With repeater hubs or switches, a network can span even longer distances. (...)
(...) It Can Span Long Distances A single twisted-pair cable between two computers or between a repeater hub or switch and a computer can be 100 meters. A half-duplex segment of fiber-optic cable in a 10-Mb/s system can be as long as 2000 meters, while a full-duplex segment can be as long as 5 kilometers. With repeater hubs or switches, a network can span even longer distances. (...)
Ethernet isn not very efficient when transferring small amounts of data (12/06/2007)
(...) Most chips support a low-power mode that can reduce power consumption when data isn’t transmitting. Still, I2C and some EIA-485 interfaces can have much lower power consumption overall. Using a PC for Network Communications An option worth considering for some embedded systems is to let a PC handle the network communications. (...)
(...) Most chips support a low-power mode that can reduce power consumption when data isn’t transmitting. Still, I2C and some EIA-485 interfaces can have much lower power consumption overall. Using a PC for Network Communications An option worth considering for some embedded systems is to let a PC handle the network communications. (...)
All data in an Ethernet network travels in structures called frames (12/06/2007)
(...) Some interfaces, such as I2C, are synchronous interfaces that include a clock line shared by all of the devices. With I2C, the transmitting device writes bits when the clock is low, and a receiving device reads the bits when the clock is high. Other interfaces, such as Ethernet, are asynchronous, which means that the interfaces don’t share a clock. (...)
(...) Some interfaces, such as I2C, are synchronous interfaces that include a clock line shared by all of the devices. With I2C, the transmitting device writes bits when the clock is low, and a receiving device reads the bits when the clock is high. Other interfaces, such as Ethernet, are asynchronous, which means that the interfaces don’t share a clock. (...)
In Ethernet networks that use half duplex interfaces (12/06/2007)
(...) The token-ring network described in IEEE standard 802.5 is an example of a token-passing network. Ethernet uses a media-access control method called carrier sense multiple access with collision detection, or CSMA/CD. (...)
(...) The token-ring network described in IEEE standard 802.5 is an example of a token-passing network. Ethernet uses a media-access control method called carrier sense multiple access with collision detection, or CSMA/CD. (...)
An Ethernet interface can be half duplex or full duplex (12/06/2007)
(...) A full-duplex segment can link two computers, a computer and a switch, or two switches. Full-duplex segments are common in high-speed links between switches. Inexpensive Ethernet switches have made full-duplex links popular for segments that connect computers to their networks as well. (...)
(...) A full-duplex segment can link two computers, a computer and a switch, or two switches. Full-duplex segments are common in high-speed links between switches. Inexpensive Ethernet switches have made full-duplex links popular for segments that connect computers to their networks as well. (...)
Putting together an Ethernet network (12/06/2007)
(...) But understanding something about network configurations and options can be useful in deciding what cable type and speed an embedded system’s interface should support. Components and Configurations A popular configuration for networked embedded systems follows the specification for the 10BASE-T media system in the Ethernet standard. A 10BASE-T network uses twisted-pair cables with a network speed of 10 Mb/s. (...)
(...) But understanding something about network configurations and options can be useful in deciding what cable type and speed an embedded system’s interface should support. Components and Configurations A popular configuration for networked embedded systems follows the specification for the 10BASE-T media system in the Ethernet standard. A 10BASE-T network uses twisted-pair cables with a network speed of 10 Mb/s. (...)
A network interface can not do much without a connection (12/06/2007)
(...) For example, the 10BASE-T media system uses unshielded twisted pair cable at 10 Mb/s. If you’re connecting your embedded systems to an existing network, and if the embedded system uses a different media system than the network, cable converters and multi-speed repeater hubs and switches are available. Cable Categories To simplify the task of selecting a cable type, various documents define cable categories according to performance, interconnection method, and other characteristics. (...)
(...) For example, the 10BASE-T media system uses unshielded twisted pair cable at 10 Mb/s. If you’re connecting your embedded systems to an existing network, and if the embedded system uses a different media system than the network, cable converters and multi-speed repeater hubs and switches are available. Cable Categories To simplify the task of selecting a cable type, various documents define cable categories according to performance, interconnection method, and other characteristics. (...)
Networks of all three speeds can use cable (12/06/2007)
(...) The conductors may be solid or stranded. A stranded conductor, which consists of many small-diameter wires, can withstand repeated flexing and is a good choice for patch cords and other uses where you’re likely to move or reroute the cable frequently. A solid conductor, which is a single, larger-diameter wire, has better electrical performance but may break after repeated flexing. (...)
(...) The conductors may be solid or stranded. A stranded conductor, which consists of many small-diameter wires, can withstand repeated flexing and is a good choice for patch cords and other uses where you’re likely to move or reroute the cable frequently. A solid conductor, which is a single, larger-diameter wire, has better electrical performance but may break after repeated flexing. (...)
There are two common pinouts for the RJ 45 connectors (12/06/2007)
(...) You can use cables with different pinouts in a network, but to avoid confusion when troubleshooting, it’s best to standardize on a single pinout and use it throughout if possible. Most RJ-45 connectors are designed for use with either solid or stranded conductors, but not both. If you’re making your own cables, be sure to use connectors that match the conductor type and are rated for your cable category or better. (...)
(...) You can use cables with different pinouts in a network, but to avoid confusion when troubleshooting, it’s best to standardize on a single pinout and use it throughout if possible. Most RJ-45 connectors are designed for use with either solid or stranded conductors, but not both. If you’re making your own cables, be sure to use connectors that match the conductor type and are rated for your cable category or better. (...)
Fiber optic cables do not use electrical current (12/06/2007)
(...) Immunity to electromagnetic interference. When a copper wire carries data, the varying currents in the wire cause a magnetic field to emanate from the cable. If a conductor’s magnetic field overlaps another conductor’s magnetic field, the signals couple, or link together via magnetic induction. (...)
(...) Immunity to electromagnetic interference. When a copper wire carries data, the varying currents in the wire cause a magnetic field to emanate from the cable. If a conductor’s magnetic field overlaps another conductor’s magnetic field, the signals couple, or link together via magnetic induction. (...)
Specifications for fiber optic cable (12/06/2007)
(...) The diameters recommended by the IEEE 802.3 standard for multimode fiber are 62.5 μm for the core and 125 μm for the cladding. (...)
(...) The diameters recommended by the IEEE 802.3 standard for multimode fiber are 62.5 μm for the core and 125 μm for the cladding. (...)
To reduce problems caused by electromagnetic interference (12/06/2007)
(...) Cables To reduce problems caused by electromagnetic interference, use fiber-optic cable or shielded twisted-pair cable. In environments where there is high-frequency electrical noise, Category 5 cable may be a better choice than Category 5e or Category 6 cable, which are more sensitive to high-frequency noise. The TIA is developing a standard for industrial-grade twisted-pair cable, tentatively called Category 5i cable. (...)
(...) Cables To reduce problems caused by electromagnetic interference, use fiber-optic cable or shielded twisted-pair cable. In environments where there is high-frequency electrical noise, Category 5 cable may be a better choice than Category 5e or Category 6 cable, which are more sensitive to high-frequency noise. The TIA is developing a standard for industrial-grade twisted-pair cable, tentatively called Category 5i cable. (...)
Connect ethernet interface to a wireless network (12/06/2007)
(...) 4 Gigahertz frequency band or infrared transmissions. Both allow transmitting data at 1 or 2 Mb/s. A variety of supplements to the standard describe additional options for the physical layer at higher speeds. (...)
(...) 4 Gigahertz frequency band or infrared transmissions. Both allow transmitting data at 1 or 2 Mb/s. A variety of supplements to the standard describe additional options for the physical layer at higher speeds. (...)
The different media systems use different encoding methods (12/06/2007)
(...) The data in Fast Ethernet systems is also scrambled before transmitting to provide bit patterns that reduce electromagnetic emissions. In twisted-pair Gigabit Ethernet, instead of serially transmitting the bits in the code symbols, which would take five bit times, the transmissions use a system of 5-level pulse-amplitude modulation. A code symbol is one of five defined voltage levels, and each level represents a 2-bit value. (...)
(...) The data in Fast Ethernet systems is also scrambled before transmitting to provide bit patterns that reduce electromagnetic emissions. In twisted-pair Gigabit Ethernet, instead of serially transmitting the bits in the code symbols, which would take five bit times, the transmissions use a system of 5-level pulse-amplitude modulation. A code symbol is one of five defined voltage levels, and each level represents a 2-bit value. (...)
Ethernet cable segments have maximum permitted lengths (12/06/2007)
(...) A repeater hub cuts off traffic from a failed interface or network segment so the rest of the network can continue to operate normally. The hub stops repeating an interface’s traffic if the port has either a large number of collisions or collisions that persist longer than normal. When the hub is no longer repeating the traffic from an interface, the offending interface is said to be partitioned from the rest of the network. (...)
(...) A repeater hub cuts off traffic from a failed interface or network segment so the rest of the network can continue to operate normally. The hub stops repeating an interface’s traffic if the port has either a large number of collisions or collisions that persist longer than normal. When the hub is no longer repeating the traffic from an interface, the offending interface is said to be partitioned from the rest of the network. (...)
Ethernet switch provides attachment points for connecting interfaces to a network (12/06/2007)
(...) On a switch, each port is in a separate collision domain, so the interfaces connected to one port don’t see traffic between the switch’s other ports. In many networks, the multiple collision domains provided by switches result in a less congested network. In Network article 2-23, when Interface 1 sends a frame to Interface 2, Repeater Hub 1 repeats the frame to Interfaces 2 and 3 and to Port A on the switch. (...)
(...) On a switch, each port is in a separate collision domain, so the interfaces connected to one port don’t see traffic between the switch’s other ports. In many networks, the multiple collision domains provided by switches result in a less congested network. In Network article 2-23, when Interface 1 sends a frame to Interface 2, Repeater Hub 1 repeats the frame to Interfaces 2 and 3 and to Port A on the switch. (...)
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