What is a DB9 Connector? Everything You Need to Know

What is a DB9 Connector

DB9 connectors are commonly used in serial communication. This article will focus on what is a DB9 connector and test method of DB9 connector port and introduce DB9 port in detail.

The term “DB9” refers to a common connector type, one of the connectors of the D-Subminiature or D-Sub type.

For more information, continue reading.

What is a DB9 Connector?

DB9 connector, a common type of electrical connector. The term “DB9” refers to a common connector type, one of the D-Subminiature or D-Sub types of connectors. DB9 has the smallest “footprint” of the D-Subminiature connectors contain 9 pins or 9 holes, depending on whether they are male or female.

The DE-9 D-sub 9-pin connector is often mistakenly referred to as the “DB-9” connector. The “E” refers to the shell size. A “DB-25” connector has a “B” size shell, but the common nine-pin connector is smaller and has an “E” size shell.

Read More: What is RS232 Connector?

Where Are DB9 Connectors Used?

What is a DB9 Connector

DB9 connectors were once very common on PCs and servers.

The EIA/TIA 232 serial interface standard, which established the purpose of each of the nine pins as a standard, allowed different companies to incorporate DB9 connectors into their products.

For serial peripheral devices like keyboards, mice, joysticks, etc., DB9 connectors were frequently used. Additionally, they are utilized for data connectivity on DB9 cable assemblies.

Modern interfaces like USB, PS/2, Firewire, and others have largely supplanted the DB9 in use today. However, there are still many legacy devices that use the DB9 interface for serial communication.

How to Test the Quality of the Serial Port Cable?

Directly test 2/3/5 pins on a multimeter to see if the two ends are connected.

Put the multimeter into the pin air to measure the female head. Due to the relatively thick measuring end of the multimeter, it is necessary to weld two relatively thin metal pins, or pins with resistance to the pins of the multimeter, to facilitate the measurement of the female head.

Measure 2/3/5 of the serial cable using a multimeter. Cross-wire 2 to 3, 3 to 2, 5 to 5 for measurement, meaning the 2 on one end of the cross serial port is measured at the other end of 3. When measuring, use a straight connection, 2/3/5 corresponds to 2/3/5.

The procedure for using the serial port assistant to send and receive data is to connect RXD to TXD and TXD to RXD, short-circuit the DB9’s 2/3 pin using the serial port assistant, and send data using the serial port assistant. If there is no problem with the serial port, self-transmit and self-receive can be realized.

Summary: What is a DB9 Connector

In fact, DB9 connector is a common electrical connector, is one of the common D-Sub connectors are used.

The DB9 model of D-Subminiature connector is the smallest; the male DB9 connector has 9 pins, while the female DB9 connector has 9 pin holes.

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Is DB9 and VGA the Same?

The VGA connector can use either a traditional DB9 connector or—more frequently—a DB15 style connector. … The VGA connector (15 pin) is still widely used and while it was originally used to carry a 640 x 480 pixel format it is used to carry a variety of geometries including HDTV formats. An analog standard is VGA.

What Does DB in DB9 Stand For?

Multiple Aston Martin models bear the DB moniker, which is actually an acronym for David Brown, who bought the company in 1947.

What is a D-sub Connector Used For?

External device connections to computers are made using D-Sub ports. Some contemporary computers still have them, despite the fact that they are an older form of connection. As faster connection technologies like Thunderbolt and USB take over, these ports are gradually being replaced.