I'm uncertain which port I need to use to make a successful LapLink connection. Can you help?
Cause
Solution
Laplink connections can be made over 3 types of cables; Serial, Parallel and USB. Certain
operating systems do not support each cable type, however. For a complete listing of Laplink-brand
cable options (including Windows compatibility), please Technical Document # 708:
Which Cable do I Have?
A
serial port is male in gender, and has either 9 pins or 25 pins. The shape of the
port is slightly D-shaped. A serial computer port may be used for a mouse, external modem, scanner,
or other linking software such as for a personal data assistant (PDA).
Note: Do not mistake the computer's Parallel port for a serial port. Only very old computers
have a 25-pin serial port. You cannot attach the wide end of the Laplink serial cable to a parallel
port, nor can you attach a gender-changer adapter to force the cables to connect. This is not
supported by Laplink technicians and will not work since the port communication method is different
between serial and parallel ports.
On most computers, there are 2 ports and they can be marked as COM, SER, with a symbol
representing 10101, or completely unmarked. ON moderately old computers, is also very common for
computer manufacturer’s to have installed 2 physical serial ports, but to leave one port disabled
in the BIOS. On newer computers, there may be onely one serial port, or none at all (especially on
a lpatop). Also, for newer computers, it's not uncommon for the serial port to be left disabled in
the BIOS, which frees up the resources for other devices. Consult your product specs or PC
manufacturer for more information.
Before using a serial port and LapLink's blue cable to make a connection, you need to locate
a port that is available physically on the back of the computer and enabled within Windows
configuration. Note: Laplink technicians will not support any connection using special port
adapters or gender-changer devices. If both of your PC's do not have compatible, functional serial
ports, you must switch to a different cable type or connection method.
There are 4 steps to naming the external serial ports on a computer:
-
Count the number of serial devices on the back of the computer. These include
external serial ports and internal modems. The phone jack ports on a card in a slot can identify an
internal modem. An serial port may have a mouse or hand-held computer cradle attached to it.
-
See how Windows is detecting the available devices from Device Manager:
- Open Device Manager. See
Technical Document 359: How to Open Windows Device
Manager for more information.
- Locate the
Modem line, click on the
plus (+) sign to expand,
- Click to highlight on the name of the installed modem.
- Click on Properties, and then the Modem tab. The name of the modem's port will be listed. Write
down this information.
- Click on OK to close the modem properties.
- Locate the Ports (COM and LPT) line, click on the plus (+) sign to expand. The ports recognized by Windows will be listed here. Write down any port names that are listed as Communications Port (COMx), where x is the number of the port.
- Open Device Manager. See
Technical Document 359: How to Open Windows Device
Manager for more information.
-
If the computer has an infrared port, it's port name needs to be determined. This
is usually configured in the computer's BIOS utility.
Note: Some laptop computers use a single address for both the external serial port and the infrared port, and expect the user to 'toggle' between the two port types. For more specific information about IBM ThinkPad computers and this issue, see Technical Document 113, How to Enable Serial Ports on an IBM ThinkPad.
-
Compare the results. There must be one port name for each serial device. If there
are more ports than port names, then one of the serial ports is disabled in the computer's BIOS.
Consult your computer's user guide for steps on how to enable the port.
If all ports can be accounted for, but you are still uncertain as to how the ports are named, systematic trial and error is the best method to use. For example, two unnamed ports are on the computer, and Windows says that they are named COM2 and COM3. Using LapLink, enable first COM2, then COM3 in Port Setup. With the cable attached to a port, see if LapLink connects. If so, then mark the attached port as COM2. If not, return to Port Setup and try COM3. If neither enabled port makes a connection, try moving the cable to the other port and begin again.
A
parallel port is female in gender, and has 25 pins. The shape of the port is
slightly D-shaped. This is the same port as where your printer attaches. On most computers, there
is only 1 port and it can be marked as LPT or with a printer symbol.
Note: The LapLink parallel cable is proprietary, and must be used to connect over
the LPT port.
Before using a parallel port and LapLink's yellow cable to make a connection, you need to
locate a port that is available physically on the back of the computer and enabled within Windows
configuration. It is very unusual for more than one LPT port to be installed on a computer and if
so, has usually been done by a computer owner rather than the manufacturer. Using the information
from Device Manager's Ports (COM and LPT) line as described above, it is easy to determine the port
name for a parallel port. If you're still uncertain, check the settings for your printer.
USB: A USB port is a slot port, approximately ½" long. On most computers there are
2 ports, and can be marked with a symbol that represents daisy chaining or networking. This type of
port will be found only on computers that have been built after 1997.
Before using a USB port and LapLink's purple or gold cables to make a connection, you need to
locate a port that is available physically on the back of the computer and enabled within Windows
configuration. USB ports are not named in the same manner as serial or parallel ports. To confirm
that a computer's USB ports are available, use the computer's user guide for steps on how to check
the computer BIOS. Additionally, check Device Manager to ensure that it lists the Universal Serial
Bus as a device.
Note: LapLink USB cables are proprietary and must be used for connections using the USB
ports. Several USB cables have been released by LapLink, Inc. See our
Cable Drivers page for more information.
If you have problems making a cable connection, see the following:
-
Technical Document 101: LapLink Serial Connection
Troubleshooting
-
Technical Document 123: Troubleshooting a Parallel Cable
Connection with LapLink Application
-
Technical Document 188: LapLink Fails to Connect Using the
USB Network Cable
- Technical Document 205: Troubleshooting a USB connection
Product: Legacy Product
KB: 117
Last updated: Sep 15, 2008
Keywords:
How To: Windows
Cable: Parallel
Cable: USB (original)
Cable: USB Network (gold)
Connections: Cable
Cable: USB Network
Product: Compatibility
Cable: Serial
Platforms:
- WinVista
- WinXP
- WinMe
- Win2K
- Win98/SE
- Win98FE
- WinNT
- Win95
Wildcards (internal use):
- How To
- Windows
