接口1394接口（1394 interface）

1394接口 1394 interface

In 1995, the American Institute of electrical and ElectronicEngineers (IEEE) developed the IEEE1394 standard, which is aserial interface, but it provides the same service as a parallelSCSI interface, and its cost is low. It is characterized by fasttransmission, now identified as 400Mb/s, and later it isexpected to increase to 800Mb/s, 1.6Gb/s, 3. 2Gb/s. So there isno problem transmitting digital image signals. The distancetransmitted by cable is now 4.5m, and further extended to 50m.At present, in practical applications, when the IEEE 1394 cableis used, the transmission distance can reach 30m; while themulti-mode fiber adaptor used by NEC is developed, thetransmission distance of multimode fiber can reach 500m.In 1995, the American Institute of electrical and ElectronicEngineers (IEEE) developed the IEEE1394 standard, which is aserial interface, but it provides the same service as a parallelSCSI interface, and its cost is low. It is characterized by fasttransmission, now identified as 400Mb/s, and later it isexpected to increase to 800Mb/s, 1.6Gb/s, 3. 2Gb/s. So there isno problem transmitting digital image signals. The distancetransmitted by cable is now 4.5m, and further extended to 50m.At present, in practical applications, when the IEEE 1394 cableis used, the transmission distance can reach 30m; while themulti-mode fiber adaptor used by NEC is developed, thetransmission distance of multimode fiber can reach 500m.Catalogbrief introduction

Standard setting processafter

Physical characteristicsapplicationequi pment

Layered protocol

The specific function link layer of each layerphysical layer

Treatment layer

Introduction to synchronous transmission

Standard setting processafter

Physical characteristicsapplicationequi pment

Layered protocol

The specific function link layer of each layerphysical layer

Treatment layer

Synchronous transport expansion edits this section

1394 interface

In 1995, the American Institute of electrical and ElectronicEngineers (IEEE) developed the IEEE1394 standard, which is aserial interface, but it provides the same service as a parallelSCSI interface, and its cost is low. It is characterized by fasttransmission, now identified as 400Mb/s, and later it isexpected to increase to 800Mb/s, 1.6Gb/s, 3. 2Gb/s. So there isno problem transmitting digital image signals. The distancetransmitted by cable is now 4.5m, and further extended to 50m.At present, in practical applications, when the IEEE 1394 cableis used, the transmission distance can reach 30m; while themulti-mode fiber adaptor used by NEC is developed, thetransmission distance of multimode fiber can reach 500m. In theIEEE 1394-2000, which was officially adopted in the spring of2000, the maximum data transmission rate can reach 1.6Gb/s, andthe maximum length of the connecting cables between adjacentdevices can be extended to 100m.

Edit the standard setting process of this paragraph

IEEE1394' s predecessor was written by Apple Computer (Apple)

in 1986. Apple Corp called it "FireWire" and registered it asits trademark. And Sony calls it i.Link. TI calls it Lynx. Asa matter of fact, the trade names mentioned above refer to thesame technology, that is, IEEE1394. FireWire completed in 1987,1995 by IEEE IEEE1394-1995 as technical specifications, beforemaking the serial interface standard, IEEE has developed 1393standards, so there will be 1394 of the serial number to it,its full name is IEEE1394, referred to as 1394. Because thereare some vague definitions in IEEE1394-1995, and then asupplementary file, P1394a, is used to clarify the doubt,correct the mistake and add some functions. In addition, theinterface standards for adding new functionality are discussedthrough P1394b. As a workgroup standard, P1394b is a hightransmission rate and long distance version of IEEE1394, whichhas a single channel bandwidth of 800Mb/s. In this scheme, animportant feature is that different transmission media can beused at different transmission distances and transmissionrates.

Edit this passage

FireWire was completed in 1987, and was designated as theIEEE1394-1995 specification by IEEE in 1995, prior to thedevelopment of this serial interface standard,

IEEE has developed 1393 standards, so the number 1394 is givento it. Its full name is IEEE1394, or 1394. Because there aresome vague definitions in IEEE1394-1995, and then asupplementary file, P1394a, is used to clarify the doubt,correct the mistake and add some functions. In addition, theinterface standards for adding new functionality are discussed

through P1394b. As a workgroup standard, P1394b is a hightransmission rate and long distance version of IEEE1394, whichhas a single channel bandwidth of 800Mb/s. In this scheme, animportant feature is that different transmission media can beused at different transmission distances and transmissionrates. The network equipment carries on the signal exchangethrough the digital interface. When connecting multiplemachines, because the signal of audio and video, control avariety of interfaces, so the information transmission mode,transmission speed, transmission capacity, with the number ofmachines, can be connected to the cable length, are the mainaspects to consider. Although theworldhas IEEE1394, universalserial bus (USB) and other digital interfaces, but with theabove criteria, the most important is IEEE1394. As anindustrial standard high-speed serial bus, IEEE1394 has beenwidely used in digital cameras, digital cameras, TV set topboxes, home game consoles, computers and their peripheralequipment. A new generation of products such as DVD, hard diskrecorders, etc. will also use IEEE1394. Its extensive use inthe digital video and audio consumer market has openedup a fulldigital production environment for the home market and even theprofessional market. IEEE1394 interface has been used in somemanufacturers of video cameras, such as Sony introduced DVCAMseries video recording equipment, Panasonic Corp launchedDVCPRO25 series devices. Other manufacturers have alsointroduced their own camera products, which will push theapplication of the 1394 interface to new heights.

Edit this paragraph of physical features

IEEE1394 is a serial digital interface, and some might argue

that a parallel bus such as IDE or PCI is not used Because morewires will provide greater bandwidth. In fact, parallel portsare very complex and require more software control than theserial buses, and the system overhead is very large. Therefore,parallel interfaces are not necessarily able to provide fastertransmission rates. In addition, the price is also a factor.More control software and connecting wires increase the costof technology implementation. Moreover, parallel wires areprone to signal interference, and solving this problem alsorequires additional cost. Another advantage of the serial busis saving space relative to the parallel bus. The series lineis smaller and more convenient to use. The IEEE1394 interfacehas two types of 6 pins and4pins. The 6 angled joint is 6 pins,and the small four angle joint is 4 stitches. The earliestIEEE1394 interface developed by Apple Corp is a 6 pin, later,SONY company took a fancy to its characteristics of high speeddata transmission, the 6 pin interface early was modified andre designed in the 4 pin interface we are now common, and namediLINK. This connector requires a converter if it is to beconnected to a standard 6 wire cable. The difference betweenthe two interfaces is whether the wires can be wired to theconnected device. In the 6 pin interface, 4 pins are used totransmit the data signal line, and the other 2 pins are powerlines which are connected to the connected equipment. Since1394 is a serial bus andwhen data is transmitted fromone deviceto another, if a device suddenly turns off or fails, it willdestroy the entire data path. Cable transmission powerconnector will make the circuit work for each device, adoptsthe design of a transmission line of power, no matter how theequipment condition, continuous signal transmission can beguaranteed, it is very important to the serial signal. For low

power equipment, the power supply in the cable meets all thepower requirements, so there is no need to have an externalpower connector. This is the advantage of a transmission powersupply. Transmission of two lines of power, the voltage betweenthem is generally 8 ~40V, maximum current 1.5A, the supply ofphysical layer power. To provide electrical isolation,Transformer or capacitor coupling is often used. Transformercoupling provides 500V voltage with low cost; capacitivecoupling provides 60V potential differential isolation. Ofcourse, not all cases have to transmit power. Sony company asa representative of the digital video recorder in theintroduction of the use of second kinds of interface design,the cable used than the first kind of finer. The interface is4 cores, that is, twisted pair only and does not contain power.The 4 pin interface eliminates the need for 2 power lines,leaving only 4 signal lines.

Edit this paragraph application

The network equipment carries on the signal exchange throughthe digital interface. When connecting multiple machines,because the signal of audio and video, control a variety ofinterfaces, so the information transmission mode, transmissionspeed, transmission capacity, with the number of machines, canbe connected to the cable length, are the main aspects toconsider. Although theworldhas IEEE1394, universal serial bus(USB) and other digital interfaces, but with the above criteria,the most important is IEEE1394. As an industrial standardhigh-speed serial bus, IEEE1394 hasbeenwidely used in digitalcameras, digital cameras, TV set top boxes, home game consoles,

computers and their peripheral equipment. A new generation ofproducts such as DVD, hard disk recorders, etc. will also useIEEE1394. Its extensive use in the digital video and audioconsumer market has opened up a full digital productionenvironment for the home market and even the professionalmarket. IEEE1394 interface has been used in some manufacturersof video cameras, such as Sony introduced DVCAM series videorecording equipment, Panasonic Corp launched DVCPRO25 seriesdevices. Other manufacturers have also introduced their owncamera products, which will push the application of the 1394interface to new heights. In applications, in general, limitedby the configuration interface space, the 6 pin interface isused primarily for ordinary desktop computers. Nowadays manymotherboards integrate this interface, especially the Applecomputer. This kind of interface is used inmost computers, suchas notebook computer and all-in-one computer, etc. , most ofthem use 4 pins. In addition, in the digital cameras and otherproducts and appliances, the use of 4 needles are also common.The 4 pin interface is much smaller in appearance than the 6pin. Compared with the 6 pin interface, the 4 pin interface doesnot provide the power pin, so the power supply is not available,but the advantage is obvious: it is small ! Especially recently,a laptop computer and a DV towards miniaturization andultra-thin development, like the IP series digital camera, SONYrecently launched a small, high degree of integration, on sucha machine if the 6 pin interface, it is very awkward. In addition,the DV 1394 interface is mainly used to transmit image data,so there is no power supply. But if you are adding an externalhard drive, the 6 pin of the 1394 terminal is very necessary,first of all, the external hard disk volume is relatively large,so it does not care about the size of the interface. Second,

the external hard disk needs power supply when running, andrequires a very high speed of transmission. At this point, the6 pin 1394 interface with power supply is necessary. In thisregard, Apple' s iPOD is more representative, on the one hand,through the 1394 interface to transfer files, on the other hand,it also automatically charging through the FireWire cable.Although IEEE-1394 can supply power to the feeder through aseries connection, it is far from enough for all connectiondevices to be powered only by wires. For example, hard drives,such as hard drives, have difficulty getting adequate powerfrom the devices they access. Take HotDrive, the Evergreen, forexample. If the hard disk is connected to the PC, it doesn'tneed any external power supply, but it needs an external powersupply if it is connected to the laptop. To sum up, the twoIEEE1394 interfaces are different, so we can not say who isbetter than anyone else. However, here, but also to tell youa small problem, the market is not only four for four needles,six for sixpin transmissioncable, there are six needle to fourpin transmission cable. However, the speed of the IEEE1394interface is very fast,

So that the connection cable for shielding requirements is veryhigh, so the market IEEE1394 line is not long, probably thelongest is more than 3 meters.

Edit this section of equipment

External equipment: external hard disk, external drive, MO,card reader. Digital video player: early versions of iPod onlyFireWire interface, from 2003 launch of the third generationbegan to support the USB interface, in September 2005 at the