Data communication system, data communication request device, and data communication response device

Abstract

Provided is a data communication system capable of switching the communication scheme without lowering the communication efficiency. In a data communication system in which a communication path connecting a first device and a second device is used, either full-duplex communication or half-duplex communication is selected, and data communication is performed, the first device transmits a first communication flag indicating whether half-duplex communication is specified to correspond to the communication processing capacity of the first device over a communication path to the second device. Based on the communication processing capacity of the second device, the second device transmits a second communication flag indicating whether half-duplex communication is specified over the communication path to the first device. Based on the first communication flag and the second communication flag, the first device and the second device select the communication scheme corresponding to both communication processing capacities of the full-duplex communication and the half-duplex communication by a procedure mutually determined in advance, and perform the data communication by using the selected communication scheme.

Description

technical field [0001] The present invention relates to a technique related to selection of a communication method in a data communication system including a plurality of communication devices connected via a communication path capable of full-duplex communication and half-duplex communication. Background technique [0002] In recent years, with the advancement of semiconductor miniaturization / high-speed technology, the amount of data communicated between LSIs mounted between devices or in devices tends to increase gradually. On the other hand, terminals (pads) of LSIs that affect assembly costs ) are strictly restricted. [0003] As the communication method used under such constraints, a half-duplex communication method and a full-duplex communication method are listed. In general, the full-duplex communication method, which is easy to control, can increase the speed. However, in the full-duplex communication method, there is a problem that the frequency band used for the ...

AI Technical Summary

Problems solved by technology

[0007] However, in the technology disclosed in Reference 1, since the communication mode is determined between the communication devices only based on whether transmission requests from both parties are simultaneously detected, effective communication may not be possible in some cases.

[0008] For example, in the case where a communication device whose transmission processing capability is equal to or less than the frequency band of one communication path performs half-duplex communication data transmission, since the one communication device occupies two communication paths exceeding the transmission processing capability for transmission, Therefore, the underflow of the sending buffer occurs, so that the sending and receiving are stopped, and the communication efficiency is reduced.

[0009] And, similarly, when one communication device whose reception processing capability is equal to or less than the frequency band of one communication path performs half-duplex communication data reception, since the one communication device occupies two communication paths exceeding the reception processing capability for Receive, so the receive buffer overflows, causing data loss

Therefore, when data loss is caused, a retransmission step is required, and communication efficiency is greatly reduced

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