Definition of DB9 pin in uart,can,rs485

Today check DB9 signal, suddenly found this kind of problem actually need Baidu to solve, mood disconsolate, then Cheng Zhang Finishing, for later use.

DB9 's male and female are as follows:

　　

Need to pay attention to the definition of male and female, more impressive male, because with more, pin serial number has been deeply imprinted in my mind. if the female is docked with the male, the pin definition is exactly one by one corresponding, so the pin number of the female base is inverted opposite the male header. That is, if the female base is placed in the way of the male, 12345 of the serial number and 54321 of the serial number is one by one corresponding. The serial number of 6789 and 9876 corresponds to one by one. Note whether the male or female are ordinal 1 close to the ordinal 6, the ordinal 5 is close to the ordinal 9.

--------------------------------------------------------------------------------------------------------------- --------------------------------------------------------------------------------------------------------------- --------------------------------------------------------------------------------------------------------------- -------------------

The DB9 UART definition male is 2-RX,3-TX,5-GND, the corresponding parent is 2-TX,3-RX,5-GND, this is to enable the device between TX and RX one by one corresponding to each other.

　　

--------------------------------------------------------------------------------------------------------------- --------------------------------------------------------------------------------------------------------------- --------------------------------------------------------------------------------------------------------------- -------------------

The RS485 definition of DB9. The RS485 commonly used half-duplex two-wire interface is defined as, 1-data-, 2-data+, 5-gnd. Because of the RS485 data+ and data+ corresponding, data-and data-one by one corresponding, so RS485 male and female head does not exist the situation of signal inconsistency.

The 4-wire RS485 has several different naming methods: The British logo is the TDA (-) TDB (+) RDA (-) RDB (+) GND, and the American logo is y Z A B gnd;

--------------------------------------------------------------------------------------------------------------- --------------------------------------------------------------------------------------------------------------- --------------------------------------------------------------------------------------------------------------- -------------------

DB9 can interface definition: the signal pin in 2 and 7, because CAN Can_h and can_h corresponding, can_l and can_l one by one corresponding, so RS485 male and female head does not exist the situation of signal inconsistency.

　　

Well, today's harvest is a summary of the completion, refueling.

Definition of DB9 pin in uart,can,rs485