Communication circuit, communication control method, circuit board, and air conditioning system

A communication control method applied to a communication circuit,

• wherein the communication circuit includes:
• a first communication node including:
• a first control chip including a detection port;
• and
• a first communication chip connected to the first control chip and configured to transmit a differential signal, the first communication chip including an output port to output a level signal obtained from the differential signal to the first control chip, and the output port being connected to the detection port;
• a second communication node including:
• a second control chip;
• and
• a second communication chip connected to the second control chip and configured to transmit the differential signal, the second communication chip being connected to the first communication chip through a first signal line and a second signal line;
• and
• a voltage division assembly connected to the first signal line and the second signal line, and configured to cause a voltage value of the first signal line to be higher than a voltage value of the second signal line when the first signal line and the second signal line are in an idle state;
• the communication control method comprising:
• acquiring, by the first control chip through the detection port, a level signal output by the output port when the first signal line and the second signal line are in the idle state;
• and
• determining, by the first control chip, a correctness of a connection polarity between the first communication chip and the second communication chip according to the level signal output by the output port.

A communication circuit comprising:

• a control chip;
• and
• a communication chip connected to the control chip and configured to transmit a differential signal through a first signal line and a second signal line, the communication chip including an output port to output a level signal obtained from the differential signal to the control chip;
• wherein the control chip includes a detection port connected to the output port to acquire the level signal output by the output port, and the level signal output by the output port is used for determining a correctness of a connection polarity between the communication chip and the first signal line or the second signal line.