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Ports

Dell™ Technology Guide

USB Port

The Universal Serial Bus (USB) is an external bus standard that supports data transfer rates of 480 Mbps in case of USB 2.0. USB gives you a single, standardized way to connect many devices to your computer. USB also supports Plug-and-Play installation and hot swapping.

The USB standard uses A and B connectors to avoid confusion:

• Connectors A head upstream toward the computer.
  
  
• Connectors B head downstream and connect to individual devices.
  
  

Pin	Signal
1	USB5V+
2	USBP–
3	USBP+
4	GND

IEEE 1394 Port

Like the USB, IEEE 1394 is a serial data transfer protocol and supports hot swapping. While the USB 2.0 technology supports speed only upto 480 Mbps, the IEEE 1394b supports speed upto 800 Mbps. IEEE 1394 is preferred for high bandwidth applications such as connecting digital video cameras and external hard drives.

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Pin	Signal
1	TPB–
2	TPB+
3	TPA–
4	TPA+

RS232 Serial Port

A serial port is a serial communication physical interface through which information transfers in or out one bit at a time. Serial port is usually identified with RS-232 standard compliant hardware. Some of the devices that commonly use serial port are dial-up modems, printers, and serial mice.

Pin	Signal
1	CD
2	RD
3	TD
4	DTR
5	SG
6	DSR
7	RTS
8	CTS
9	RI

Parallel Port

A parallel port is a parallel communication physical interface through which information transfers in or out 8 bits of data (1 byte) at a time. These 8 bits are transmitted parallel to each other, as opposed to the same eight bits being transmitted serially (all in a single row) through a serial port. A parallel port is also known as a printer port or Centronics port and is commonly used to connect to a printer.

Pin	Signal	Pin	Signal
1	/STROBE	14	/AUTOFD
2	D0	15	/ERROR
3	D1	16	/INIT
4	D2	17	/SELIN
5	D3	18	GND
6	D4	19	GND
7	D5	20	GND
8	D6	21	GND
9	D7	22	GND
10	/ACK	23	GND
11	BUSY	24	GND
12	PE	25	GND
13	SEL

eSATA Port

SATA (Serial Advanced Technology Attachment) is a computer bus primarily designed for transfer of data between a computer and mass storage devices such as hard disk drives and optical drives.

External SATA or eSATA, users can now utilize shielded cable lengths up to 2 meters outside the PC to take advantage of the benefits the SATA interface brings to storage. eSATA provides more performance than existing solutions (up to 6 times faster than existing external storage solutions: USB 2.0, & 1394) and is hot pluggable.

eSATA is commonly used for External Direct Attached Storage for notebooks, desktop, consumer electronics and entry servers.

Pin	Signal
1	GND
2	DR+
3	DR-
4	GND
5	DT+
6	DT-
7	GND

Modem

A modem port connects an internal modem to a telephone line. A modem is used to connect a computer to the Internet by making a data call over phone lines to an Internet Service Provider (ISP).

Usually, there are two modem ports side by side. The one marked line (or with a line symbol) is connected to the telephone line connector. The one marked phone (or with a phone symbol) can optionally be connected to the telephone handset if you want to use a telephone on the same connector.

If your computer does not have an internal modem installed, you will not see these ports. You may also see an ethernet port, see Ethernet Port. It looks similar to a modem port but is wider.

Pin	Signal
1	R-
2	T+

Ethernet Port

An ethernet port uses twisted pair conductors for networking and faster Internet connection.

Cable plugged into this port can lead either to a network hub (a junction box that can wire lots of network cables together), directly to a cable modem, or a DSL modem or to an Internet gateway which shares a fast Internet connection between computers.

Data moves through these at speeds of either 10 Mbps, 100 Mbps, or 1000 Mbps depending on the speed supported by the network card in the computer. When in use, lights on these devices flicker.

The ACT light flickers when data moves through the network to or from the port. The 10 or 100 light denote data speed. 10 denotes data moving across the network at 10 Megabits per second while 100 denotes data moving at 100 Megbits per second.

Pin	Ethernet 10/100 Base -T Signal	Pin	Gigabit Ethernet Signal
1	Transmit +	1	Transmit/Receive 0 +
2	Transmit	2	Transmit/Receive 0 –
3	Receive +	3	Transmit/Receive 1 +
4	NU	4	Transmit/Receive 2 +
5	NU	5	Transmit/Receive 2 –
6	Receive –	6	Transmit/Receive 1 –
7	NU	7	Transmit/Receive 3 +
8	NU	8	Transmit/Receive 3 –

Keyboard and Mouse Port (PS2)

The PS/2 standard, introduced by IBM in 1987, stands for Personal System/2. PS/2 port is commonly used to plug in a keyboard or mouse.

Pin	Signal
1	Keyboard/mouse data
2	(Reserved)
3	Ground
4	Keyboard/mouse power (+5 V)
5	Keyboard/mouse clock
6	(Reserved)

VGA Port

Video Graphics Array (VGA) port supports the basic graphic hardware before a device-specific driver is loaded into the computer.

Pin	Signal	Pin	Signal
1	RED Video	9	DDC 5V+
2	GREEN Video	10	SYNC GND
3	BLUE Video	11	MONITOR_DETECT–
4	NC	12	DDC_DATA (SDA)
5	GND	13	Horizontal SYNC
6	RED Video GND	14	Vertical SYNC
7	GREEN Video GND	15	DDC_CLK (SCL)
8	BLUE Video GND

DVI-I Port

DVI-I (Digital Video Interface-Integrated) port supports both analog signals and digital signals in a single cable. The cable can transmit either a digital-to-digital signal or an analog-to-analog one, but it will not transmit crossovers of either one (digital-to-analog or analog-to-digital). If you have a DVI-I port on your video card, you can connect most DVI-D (Digital Video Interface-Digital) or DVI-A (Digital Video Interface-Analogue) devices without the need for a separate adapter.

Pin	Signal	Pin	Signal
1	TMDS DATA2–	13	TMDS DATA3+
2	TMDS DATA2+	14	+5V
3	TMDS DATA2/4 SHLD	15	GND (FOR +5V)
4	TMDS DATA4–	16	HOT PLUG DETECT
5	TMDS DATA4+	17	TMDS DATA0–
6	DDC CLK	18	TMDS DATA0+
7	DDC DATA	19	TMDS DATA0/5 SHLD
8	ANALOG VERT SYNC	20	TMDS DATA5–
9	TMDS DATA1–	21	TMDS DATA5+
10	TMDS DATA1+	22	TMDS CLK SHLD
11	TMDS DATA1/3 SHLD	23	TMDS CLK+
12	TMDS DATA3–	24	TMDS CLK–

S-Video TV-Out Port

SUPER Video (S-Video), also known as Y/C is an analog video signal that carries the video data as two separate signals, luma (brightness) and chroma (color). S-Video supports a standard definition video, but does not carry audio on the same cable. S-Video provides sharp images when using a clean DVD source. S-Video commonly connects to consumer TVs, DVD players, high-end video cassette recorders, digital TV receivers, DVRs, and game consoles.

Composite video carries (lower-quality) picture information as a single signal.

S-Video
Pin	Signal
1	GND
2	GND
3	LUMA
4	CHROMA

Composite Video
Pin	Signal
5	GND
6	CVBS
7	NC

Component Video

Component video consists of three signals.

The first is the luminance signal, which indicates brightness or black & white information that is contained in the original RGB (red green blue) signal. It is referred to as the Y component.

The second and third signals are called color difference signals indicating the quantum of blue and red signals compared to luminance. The blue component is Y-B and the red component is Y-R. Green is not transmitted as a separate signal since it can be inferred from the Y, Y-B, and Y-R combination.

Component video inputs are available on modern high-end television sets and DVD players, providing a signal quality that is superior to earlier systems such as RF, composite, and so on.

Pin	Signal
Red	Y-R (Pr)
Blue	Y-B (Pb)
Green	Y

Composite Video

Composite video is an interface for sending or receiving an analog video signal. It is a composite of several signals, LUMA, CHROMA, and SYNC (together referred to as CVSB or Composite Video Blanking and Sync). LUMA represents the brightness or luminance of the picture and includes synchronizing or SYNC pulses. CHROMA carries the color information.

Composite video interface usually connects a VHS tape player, DVD player, or game console to a television.

Composite Video
Pin	Signal
1	GND
2	CVBS

HDMI Port

The High-Definition Multimedia Interface (HDMI) PORT is a compact audio/video interface for transmitting uncompressed digital streams.

On a single cable, HDMI supports PC or TV video formats such as standard, enhanced, and high-definition video along with up to 8 channels of digital audio. It is independent of the various digital television standards.

HDMI connects digital audio/video sources such as Blu-ray Disc players, set-top boxes, personal computers, and video game consoles to compatible digital audio devices, computer monitors, and digital televisions.

Pin	Signal	Pin	Signal
1	TMDS Data2+	11	TMDS Clock Shield
2	TMDS Data2 Shield	12	TMDS Clock–
3	TMDS Data2–	13	CEC
4	TMDS Data1+	14	Reserved (N.C. on device)
5	TMDS Data1 Shield	15	SCL
6	TMDS Data1–	16	SDA
7	TMDS Data0+	17	DDC/CEC Ground
8	TMDS Data0 Shield	18	+5 V Power (max 50 mA)
9	TMDS Data0–	19	Hot Plug Detect
10	TMDS Clock+

DisplayPort™

DisplayPort is a digital display interface standard put forth by the Video Electronics Standards Association (VESA). It defines a new license-free, royalty-free, digital audio/video interconnect, intended to be used primarily between a computer and its display monitor, or a computer and a home-theater system. For more information see DisplayPort™ - Features and Benefits.

Pin	Signal	Pin	Signal
1	ML_Lane 0(p)	11	GND
2	GND	12	ML_Lane 3(n)
3	ML_Lane 0(n)	13	GND
4	ML_Lane 1(p)	14	GND
5	GND	15	AUX_CH(p)
6	ML_Lane 1(n)	16	GND
7	ML_Lane 2(p)	17	AUX_CH(n)
8	GND	18	Hot Plug
9	ML_Lane 2(n)	19	DP_PWR Return
10	ML_Lane 3(p)	20	DP_PWR

S/PDIF Port (Coaxial RCA)

Sony/Philips Digital Interconnect Format (S/PDIF) is a serial interface for transferring digital audio from CD and DVD players to amplifiers and TVs.

S/PDIF uses unbalanced 75 ohm coaxial cable up to 10 meters with coaxial RCA connectors or optical fiber terminated with a Toslink (Toshiba link) connector.

NOTE: There are no differences in the signals transmitted over optical or coaxial S/PDIF connectors—both carry exactly the same information.

S/PDIF is typically used to transmit PCM and Dolby Digital 5.1, but is not tied to any sampling rate or audio standard.

S/PDIF Port (Toslink)

Toslink usually refers to the optical version of S/PDIF.

NOTE: There are no differences in the signals transmitted over optical or coaxial S/PDIF connectors—both carry exactly the same information.

Audio Ports

Port	Signal	Connection
1	line-in connector	Use the (blue) line-in connector to attach a record/playback device such as a cassette player, CD player, or VCR. On computers with a sound card, use the connector on the card.
2	lineout/ headphone connector	Use the (green) line-out connector to attach headphones and speakers with integrated amplifiers.
3	microphone connector	Use the (pink) microphone connector to attach a personal computer microphone for voice or musical input into a sound or telephony program.
4	side surround sound connector	Use the (silver) side surround connector to attach additional speakers.
5	rear surround out	Use the (black) surround sound connector to attach multichannel-capable speakers.
6	center/LFE surround out	Use the (orange) subwoofer connector to attach a single subwoofer.

NOTE: The LFE (Low Frequency Effects) Audio channel, found in digital surround sound audio schemes, carries only low frequency information of 80 Hz and below. The LFE channel drives a subwoofer to provide extremely low bass extension. Systems not using subwoofers can shunt the LFE information to the main speakers in the surround sound setup.

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