RS-232 stands for Recommended Standard 232. It is a standard for serial binary data signals connecting between a Data Terminal Equipment (DTE) and a Data Circuit-terminating Equipment (DCE). It is widely implemented in computer serial ports communication –  roadmap for the way devices speak to each other using serial ports. RS-232 is radically identical to ITU V.24 (signal description and names) and V.28 (electrical). RS232 is an Active LOW voltage driven interface and operates at +12V to -12V.

RS232 DB25 Pinouts

Pin 1

Protective Ground

Pin 2

Transmit Data

Pin 3

Received Data

Pin 4

Request To Send

Pin 5

Clear To Send

Pin 6

Data Set Ready

Pin 7

Signal Ground

Pin 8

Data Carrier Detect

Pin 20

Data Terminal Ready

Pin 22

Ring Indicator

RS232 DB9 Pinouts

Pin 1

Data Carrier Detect

Pin 2

Received Data

Pin 3

Transmit Data

Pin 4

Data Terminal Ready

Pin 5

Signal Ground

Pin 6

Data Set Ready

Pin 7

Request To Send

Pin 8

Clear To Send

Pin 9

Ring Indicator

RS232 RJ-45Pinouts

Pin 1

Data Set Ready / Ring Indicator

Pin 2

Data Carrier Detect

Pin 3

Data Terminal Ready

Pin 4

Signal Ground

Pin 5

Received Data

Pin 6

Transmit Data

Pin 7

Clear To Send

Pin 8

Request To Send