The technician also asked me this question two days ago. I said you can't tell 485 from 232 by appearance. I don't think you need to be so persistent. As far as I know, computers generally have 232 interfaces. According to the definition of computer serial port, it should also be 232 interface. At least I haven't seen anyone's computer with 485 interface, and 485 has only been seen in PLC and man-machine interface. This is very clear. You can take it apart and look at the connector.