RS232 pinout and cables layout

Serial port interface

Serial port interface introduction

RS232 to RS232, RS232C

RS232 to RS232 connection using DB9 connectors.
RS-232 - RS-232 connection using DB25 connectors.
Serial Port to Serial Port. Possible variants and cables. DTE-DCE, DTE-DTE.

Serial port pinout and signal

The serial port is an I/O (Input/Output) device. An I/O device is just a way to get data into and out of a computer. There are many types of I/O devices such as serial ports, parallel ports, disk drive controllers, ethernet boards, universal serial buses, etc. Most PC's have one or two serial ports.

Connectors and signals
RS232 pinout and signals
Serial port pinout and signals
Full DB25 serial (RS232) port pinout and signals
DB9 pinout and signals
DB25 pinout and signals
PC DB25 serial (RS232) loopback (CheckIt)
PC DB25 serial (RS232) loopback (Norton)
PC DB9 serial (RS232) loopback (CheckIt)
PC DB9 serial (RS232) loopback (Norton)
Serial printer

Serial port cables and signals

While the normal PC hardware might well run with just Tx, Rx and Ground connected, most driver software will wait forever for one of the handshaking lines to go to the correct level. Depending on the signal state it might sometimes work, other times it might not.

Serial port and RS232 port cables and signals
Serial and RS232 port monitor cables
Serial data transfer cable
Serial (RS232) two-wire modem cable (DB25-DB25)
Serial (RS232) two-wire modem cable (DB9-DB25)
Serial (RS232) modem cable (DB25-DB25)
Serial (RS232) modem cable (DB9-DB25)
Serial (RS232) modem cable (DB9-DB15)
Null modem cable (DB25-DB25)
Null modem cable (DB9-DB25)
Null modem cable (DB9-DB9)
Serial printer cable (DB25-DB25)
Serial printer cable (DB9-DB25)

USB cables and signals

USB port sockets, connectors, cables: pinouts and signals