Data transmission device, method and system for communication

Abstract

The invention discloses a data transmission device, method and system for communication, with the advantages of electricity saving, maintained online quality, stability and no disconnection. The method comprises the steps of: referring a set value of the data transmission device, and gradually and directionally regulating a de-reinforcement of a signal to be transmitted by the data transmission device. The method also comprises the steps of: transmitting a training sequence signal with an amplitude and a preset de-reinforcement to a remote end device by the data transmission device, and receiving the training sequence signal transmitted by the remote end device. Channel decrement is estimated by using the method, a preferable de-reinforcement is set, and then the amplitude is gradually increased and then the training sequence signal is re-transmitted until the remote end device receives the training sequence signal transmitted by the data transmission device.

Description

technical field [0001] The present invention relates to a data transmission device and method for communication and its system, in particular to a data transmission device and method with a de-emphasis function and its system. Background technique [0002] Under the requirement of continuous development of signal quality and transmission speed of signal transmission devices, the bus between devices consists of first-generation ISA, EISA, VESA and Micro Channel, second-generation buses include PCI, AGP and PIC-X, and PCI Express Belonging to the third generation of high-performance I / O bus, it can be used as the interconnection of many peripheral devices on computing and communication platforms. Its applications cover mobile computing, desktop computers, workstations, servers, embedded computing and communications platform. [0003] The PCI Express architecture not only continues the advantages of the previous two generations of bus architectures, but also incorporates new c...

AI Technical Summary

Problems solved by technology

At present, the bandwidth of PCI Express data transmission and reception can reach 2.5Gbits per second. The transmission signal amplitude of PCI Express needs to take into account the length of the transmission line, signal loss and different amplitudes required by different hosts, so the output defined in the specification The amplitude has a certain size, but in fact, in most cases, it is not necessary to output a large amplitude to complete the communication of the sending and receiving signal, so outputting a large amplitude is a waste of unnecessary energy, but if it cannot automatically detect and reduce the signal amplitude , the signal amplitude is too small and there will be a danger of disconnection

[0004] In addition, in the serial connection system, since it is a one-way transmission, that is, the transmission line and the receiving line are not on the same line path, although the connection quality can be improved by adjusting the amount of de-emphasis at the transmitting end, the amount of de-emphasis at the host end corresponds to The reception quality on the device side is unknown, so it is often impossible to know the poor connection

If you check whether the negative acknowledgment (NAK) count returned by the device exceeds a critical value, you can decide whether to replace another set of de-enhancements on the host until the device does not return a NAK, although the connection quality may occasionally improve. improvement, but this adjustment was blindly tested without direction, as referenced figure 1 , which is a schematic diagram of a method for improving online quality disclosed in U.S. Patent No. 7,502,338, wherein steps 12 to 15 use dynamic adjustment of the de-enhancement amount to continuously change the setting of the de-enhancement amount, because it is impossible to know The characteristics of the circuit board or the device side, and changing the de-emphasis amount during the transmission process may cause the disconnection of the device end (that is, the device side adjusts a set of worse de-emphasis amount under the already bad setting), and in PCI In the Express system, disconnection is not allowed, so the serious consequences of possible disconnection cannot be avoided

Images