DB9 male Female header pin definition and connection

1. Introduction of physical and pin

In the development of the time will often use the serial interface, the general 9-pin serial interface is mostly. As shown in the following:

The male female head is used in the package for connecting wire. However, a 90-degree angled pin package is used for the Development Board. Such as:

Each pin is defined as:

2. Connection of male female head to MAX232

When the male head is connected to the MAX232, we will find that the definition of the 9 pins is as if the male and the female are not different except the appearance, because each pin definition is the same. It's wrong to think like this! Look carefully at the first picture will find that in the male and female connection, the male head of the 2 feet connected to the female 2 feet, male 3 feet connected to the female head 3 feet. If the PIN definition becomes the receiving end of the connection, the sending end is connected to the sender. So, for the male to be pin-defined, the female can be understood to be the pin definition she wants to receive. For example the female head 2 feet understand as she wants to connect the header to the receiving data end.

The following is an internal structure diagram of MAX232:

If using male, the connection method is: MAX232 (14,7) connection male (3), MAX232 (13,8) connection male (2).

If the female header is used, the connection method is: MAX232 (14,7) connection female (2), MAX232 (13,,8) connection male (3).

We use the connection line is usually the two ends are the female connector, both ends are male connectors, one end is the male end is a female line. Using a multimeter test will find that both ends are male or female lines, the line inside the 2,3 pin line upside down, that is, one end of the 2 feet connected to the other end of the 3 feet, 3 feet connected to the other end of the 2 feet. And one end is the male end is the female line, one end of the 2 feet connected to the other end of the 2 feet, 3 feet connected to the other end of the 3 feet.

3. The package size of the serial port

The male is the same as the female package, but the PIN number is not the same!

Male female head

Transferred from: http://blog.csdn.net/yangshuodianzi/article/details/8997478

DB9 male Female header pin definition and connection