Communication apparatus and related methods

Abstract

A communication device and related method are provided. The communication device includes a differential input port; a signal pairing unit configured to couple the differential input port to a receiving unit, wherein when the signal pairing unit operates in a first mode, a positive input port and a negative input port of the differential input port are correspondingly coupled to a positive input terminal and a negative input terminal of the receiving unit, and when the signal pairing unit operates in a second mode, the positive input port and the negative input port of the differential input port are correspondingly coupled to the negative input terminal and the positive input terminal of the receiving unit; a processing unit configured to determine whether a specific code is included in the decoded signal before a timer expires, and generate a determination result; and a control unit configured to control the signal pairing unit according to the determination result.

Description

TECHNICAL FIELD

[0001] The present application relates to communications, and more particularly to a communication device and related methods. BACKGROUND

[0002] Differential signal pairs represent digital signals by complementary voltages, which can effectively improve signal-to-noise ratio. However, if a transceiver circuit using differential signal pairs is designed, or a printed circuit board on which the transceiver circuit is located is designed, attention should be paid to the fact that the positive and negative terminals of the differential signal pairs of the transceiver circuit should be correctly coupled to the positive and negative terminals of the differential signal pairs of another transceiver. If the positive and negative terminals are coupled in reverse, the transceiver circuit cannot correctly transmit and receive signals, and the chip or the printed circuit board needs to be modified, which increases additional costs. Therefore, the above inconveniences have become problems to be solved. SUMMARY

[0003] The present application provides a communication device, comprising: a differential input port, configured to receive a differential signal from a differential output port of another communication device through a transmission line; a signal pairing unit, configured to couple the differential input port to a receiving unit, wherein when the signal pairing unit operates in a first mode, a positive input port and a negative input port in the differential input port are correspondingly coupled to a positive input terminal and a negative input terminal of the receiving unit, and when the signal pairing unit operates in a second mode, the positive input port and the negative input port in the differential input port are correspondingly coupled to the negative input terminal and the positive input terminal of the receiving unit; the receiving unit, configured to receive the differential signal to generate a received signal; a decoder, configured to decode the received signal to generate a decoded signal; and a processing unit, configured to: reset a timer, determine whether a specific code is included in the decoded signal before the timer expires, and generate a determination result; and selectively switch the signal pairing unit from the first mode to the second mode, or from the second mode to the first mode, according to the determination result.

[0004] The present application provides a method for a communication device, a differential input port of the communication device receiving a differential signal from a differential output port of another communication device through a transmission line, the method comprising: coupling the differential input port to a receiving unit in the communication device through a signal pairing unit, wherein when the signal pairing unit operates in a first mode, a positive input port and a negative input port in the differential input port are coupled to a positive input terminal and a negative input terminal of the receiving unit respectively, and when the signal pairing unit operates in a second mode, the positive input port and the negative input port in the differential input port are coupled to the negative input terminal and the positive input terminal of the receiving unit respectively; receiving the differential signal through the receiving unit to generate a received signal; decoding the received signal through a decoder to generate a decoded signal; resetting a timer; determining whether a specific code is included in the decoded signal before the timer expires and generating a determination result; and selectively switching the signal pairing unit from the first mode to the second mode or from the second mode to the first mode according to the determination result.

[0005] By the present application, the problem of reverse connection of positive and negative terminals of a differential signal can be quickly found and solved, and the verification time and the cost of modifying the design when an error occurs are reduced. BRIEF DESCRIPTION OF DRAWINGS

[0006] Various embodiments of the application are best understood with reference to the detailed description of the embodiments hereinbelow and the accompanying drawings. It should be noted that the various features of the drawings are not drawn to scale. In fact, the dimensions of certain features can have been intentionally exaggerated or reduced for the sake of clarity.

[0007] Figure 1 A schematic diagram of an embodiment of a communication device in the present application.

[0008] Figure 2 A flowchart of an embodiment of a related method of a communication device in the present application.

[0009] REFERENCE NUMERALS

[0010] 101, 103: communication device 104: signal pairing unit 106: receiving unit

[0011] 108: decoder 110: processing unit 200: flowchart

[0012] 202-212: steps DD: decoded signal RN: negative input port

[0013] RP: positive input port RXD: received signal TL: transmission line

[0014] TN: negative output port TP: positive output port DETAILED DESCRIPTION

[0015] In order to make the above objectives, features and advantages of the embodiments of the present application more clear and comprehensible, the following will be detailed with reference to the accompanying drawings.

[0016] Figure 1 A schematic diagram of an embodiment of a communication device 103 in the present application. The differential input port of the communication device 103 is coupled to the differential output port of another communication device 101 through a transmission line TL to receive differential signals. The differential input port of the communication device 103 includes a positive input port RP and a negative input port RN; the differential output port of the communication device 101 includes a positive output port TP and a negative output port TN. The transmission line TL can be a transmission line on a printed circuit board, a cable or other channel. Suppose that the transmission line TL is designed with an error such that the positive input port RP and the negative input port RN are substantially coupled to the negative output port TN and the positive output port TP respectively, which will cause the communication device 103 to fail to correctly receive data transmitted by the communication device 101. Therefore, the present application proposes to use a signal pairing unit 104 to provide a solution. It should be noted that, besides the transmission line TL, for example, within the communication device 101 or within the communication device 103, an error can also occur such that the positive input port RP and the negative input port RN are substantially coupled to the negative output port TN and the positive output port TP respectively, and such an error can also be solved by the solution of the present application.

[0017] The signal pairing unit 104 of the communication device 103 is coupled between the differential input port and a receiving unit 106, and is used to selectively operate between two modes according to the control of a processing unit 110. When the signal pairing unit 104 operates in a first mode, the positive input port RP and the negative input port RN are correspondingly coupled to the positive input end (+) and the negative input end (-) of the receiving unit 104; when the signal pairing unit 104 operates in a second mode, the positive input port RP and the negative input port RN are correspondingly coupled to the negative input end (-) and the positive input end (+) of the receiving unit 104. Therefore, no matter how the transmission line TL is designed, as long as the communication device 103 finds that the positive input port RP and the negative input port RN are not substantially coupled to the positive output port TP and the negative output port TN respectively, the signal pairing unit 104 can be used to swap the two signals input to the positive input port RP and the negative input port RN.

[0018] The receive unit 106 generates a non-differential receive signal RXD from the differential signal outputted by the signal pairing unit 104. For example, the receive unit 106 can include an operational amplifier. The decoder 108 decodes the receive signal RXD to generate a decoded signal DD according to the communication protocol corresponding to the communication device 103. The processing unit 110 generates a control signal SC to control the signal pairing unit 104 according to the decoded signal DD, the details of which are described in conjunction with Figure 2 and the following description.

[0019] Figure 2 A flowchart of an embodiment of a method related to the communication device 103 of the present application is shown in FIG. 2. Specifically, the processing unit 110 executes the flowchart 200 to control the communication device 103. In step 202, the processing unit 110 resets a timer to a certain state, for example, resets the timer to start counting from zero, and the timer will send a time-out notification after a predetermined time interval.

[0020] Generally, in a communication protocol, certain defined special codes will appear intermittently to facilitate the communication between the two parties that want to transmit. If the positive input port RP and the negative input port RN are substantially coupled to the negative output port TN and the positive output port TP, respectively, the communication device 103 will not be able to decode the special codes correctly. Therefore, the present application uses this characteristic as a basis for judgment, and pre-selects one or more groups of special codes as targets. In the 8b / 10b encoding, K28.5 is a common special code used for character alignment and expressing idle mode. Since it is impossible to not receive K28.5 for a long time under normal circumstances, K28.5 is suitable for the processing unit 110 to determine whether the mode of the signal pairing unit 104 needs to be switched.

[0021] In step 204, the processing unit 110 determines whether the special code appears in all the decoded signals DD received from the decoder 108 during the period from the time the timer is reset to the time the timer is time-out. For example, the processing unit 110 continuously compares the decoded signal DD with the special code before the timer is time-out, and if the special code is not found in the decoded signal DD before the timer is time-out, the flowchart 200 proceeds to step 206. Otherwise, if the special code is found in the decoded signal DD before the timer is time-out, the flowchart 200 proceeds to step 208. It should be noted that the special code in the present embodiment can be a group of defined codes selected from the communication protocol, or a plurality of groups of defined codes selected from the communication protocol, and the plurality of groups of defined codes can be continuous or discontinuous.

[0022] Specifically, if the signal pairing unit 104 is operating in the first mode when entering step 206, the processing unit 110 will switch the signal pairing unit 104 from the first mode to the second mode after entering step 206; otherwise, if the signal pairing unit 104 is operating in the second mode when entering step 206, the processing unit 110 will switch the signal pairing unit 104 from the second mode to the first mode after entering step 206. After leaving step 206, the flow 200 will re-enter step 202, and then re-perform step 204 with the signal pairing unit 104 switched.

[0023] In the present embodiment, the processing unit 108 will perform the connection simultaneously when receiving the decoded signal DD. As mentioned above, entering step 208 indicates that the specific code is successfully found in the decoded signal DD before the timer expires. In step 208, the processing unit 108 will also determine whether the connection between the communication device 103 and the communication device 101 is successful. If the connection is successful, it will enter step 210, in which the processing unit 108 will keep the signal pairing unit 104 in the current mode and let the communication device 103 enter the general transceiving mode. If the connection is not successful, it indicates that there is another problem that prevents the communication device 103 from successfully connecting with the communication device 101. In this case, it will enter step 212, in which the processing unit 108 will not let the communication device 103 enter the general transceiving mode. Since the mode setting of the signal pairing unit 104 is known to be correct through step 204, the processing unit 108 will not try to change the mode of the signal pairing unit 104 in step 212.

[0024] By the signal pairing unit 104 and its control mechanism, the problem of the positive and negative terminals of the differential signal being connected reversely can be quickly found and solved, and the verification time and the cost of modifying the design when an error occurs are reduced.

Claims

1. A communication device, comprising: a differential input port to receive a differential signal from a differential output port of another communication device over a transmission line; a signal pairing unit to couple the differential input port to a receiving unit, wherein when the signal pairing unit operates in a first mode, positive and negative input ports of the differential input port are coupled to a positive and a negative input of the receiving unit, respectively, and when the signal pairing unit operates in a second mode, the positive and negative input ports of the differential input port are coupled to the negative and positive input of the receiving unit, respectively; the receiving unit to receive the differential signal to generate a received signal; a decoder to decode the received signal to generate a decoded signal; a processing unit to: reset a timer, determine whether a particular code is included in the decoded signal before the timer expires, and generate a determination result; and selectively switch the signal pairing unit from the first mode to the second mode or from the second mode to the first mode according to the determination result. when the signal pairing unit operates in the first mode and the determination result indicates that the particular code is not included in the decoded signal before the timer expires, the processing unit is further to:

2. The communication apparatus according to claim 1, wherein switch the signal pairing unit from the first mode to the second mode. when the signal pairing unit operates in the first mode and the determination result indicates that the particular code is not included in the decoded signal before the timer expires, the processing unit is further to:

3. The communication apparatus according to claim 2, wherein reset the timer; and determine whether the particular code is included in the decoded signal before the timer expires while the signal pairing unit is in the second mode. when the signal pairing unit operates in the second mode and the determination result indicates that the particular code is not included in the decoded signal before the timer expires, the processing unit is further to: switch the signal pairing unit from the second mode to the first mode.

4. The communication apparatus according to claim 1, wherein when the signal pairing unit operates in the second mode and the determination result indicates that the particular code is not included in the decoded signal before the timer expires, the processing unit is further to: reset the timer; and 5. The communication apparatus according to claim 4, wherein determine whether the particular code is included in the decoded signal before the timer expires while the signal pairing unit is in the first mode. the processing unit is further to: determine whether a connection between the communication device and the other communication device is successful. when the signal pairing unit operates in the first mode, the determination result indicates that the particular code is included in the decoded signal before the timer expires, and the connection between the communication device and the other communication device is successful, the processing unit is further to:

6. The communication apparatus according to claim 1, wherein keep the signal pairing unit in the first mode and enter a general transceiving mode. ​ 7. The communication apparatus according to claim 6, wherein ​ ​ 8. The communication apparatus according to claim 6, wherein When the signal pairing unit is operating in the second mode and the determination indicates that the specific code is included in the decoded signal before the timer expires and the communication device successfully connects with the other communication device, the processing unit is further arranged to: maintain the signal pairing unit in the second mode and enter a general transceiving mode.

9. The communication apparatus according to claim 6, wherein When the signal pairing unit is operating in the first mode and the determination indicates that the specific code is included in the decoded signal before the timer expires and the communication device fails to connect with the other communication device, the processing unit is further arranged to: maintain the signal pairing unit in the first mode and not enter a general transceiving mode.

10. The communication apparatus according to claim 6, wherein When the signal pairing unit is operating in the second mode and the determination indicates that the specific code is included in the decoded signal before the timer expires and the communication device fails to connect with the other communication device, the processing unit is further arranged to: maintain the signal pairing unit in the second mode and not enter a general transceiving mode.

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