How to Use a Touch-Screen Monitor With a Serial Port

by Jeff Grundy
Jupiterimages/Comstock/Getty Images

Most of the time, when you see someone using a touch-screen monitor, it's usually a cashier at a retail establishment or a restaurant. However, touch screen monitors are useful for other applications besides ringing up sales or taking orders. For instance, touch screens are useful for kiosk systems or those used in small or confined spaces -- like a kitchen counter -- where using a mouse would be cumbersome or difficult. Some newer touch screen monitors ship with USB interfaces for the touch -- mouse -- interface, and connecting them to a computer is relatively straightforward. However, some other touch-screen monitors may have only an older serial connector type for the touch feature. Consequently, connecting and using an older touch screen monitor with a serial interface might require an adapter when paired with a newer computer.

Step 1

Power off the touch-screen monitor and the PC, if you have not already done so. Connect a USB mouse to the computer if you do not already have one installed. You must use a mouse to install the USB-to-serial adapter before connecting the touch-interface cable.

Step 2

Connect the video cable from the touch-screen monitor to the video-out port on the computer. If the connector on the video cable does not match the video-out port on the computer, use a VGA-to-DVI or DVI-to-VGA adapter as needed.

Step 3

Power on the touch-screen monitor first, then the PC. Boot into Windows and log in with an administrator username and password if prompted. After Windows loads completely and displays the desktop, connect the USB-to-serial adapter cable to empty USB port on the computer.

Step 4

Insert the USB-to-serial adapter disc into the CD/DVD drive and click the "OK" button if Windows prompts you do so. If Windows requires a driver for the adapter, it will install it from the disc automatically after you click "OK." However, for most adapter cables, Windows does not require a third-party driver disc, as it has common USB-to-serial drivers built into the operating system. Nevertheless, if prompted to install a driver for the adapter, insert the disc and allow Windows to install the required software. After Windows installs the driver, you may or may not have to reboot your computer to complete the installation of the adapter.

Step 5

Connect the male end of the DB9 serial cable to the "Touch" or "Serial" port on the back of the touch screen monitor. Plug the other end DB9 serial cable into the male adapter port on the USB-to-serial adapter.

Step 6

Insert the installation disc that came with the touch screen monitor into the optical drive of the computer and wait a few seconds for the setup wizard window to appear. Click the "Install Software," "Setup" or other similarly named button, then follow the on-screen prompts to install the Windows drivers for the touch interface. Reboot the computer when prompted.

Step 7

Launch the touch configuration program after the PC restarts. Click the "Configure," "Sync" or other similar link in the utility, then follow the prompts to synchronize the touch interface for use as mouse replacement. Save the configuration settings when prompted and exit the application.

Disconnect the USB mouse from the computer and use the touch interface on the monitor with your applications as you would a standard mouse.


  • When purchasing a USB-to-serial cable, make sure you buy one with active circuitry that performs the conversion instead of one that simply has passive connectors. Some adapter cables only convert the port connections and not the signals themselves. You can tell an active adapter from a passive one by the large oval or rectangular casing in the middle of the cable or at the serial end of the cable. This casing contains a small circuit board that performs the active signal conversion. Adapter cables such as the Gigaware USB-to-serial cable and Trendnet TU-S9 are both affordable and available for purchase at electronics retailers, such as Radio Shack.
  • If Windows requires a driver for the USB-to-serial adapter, and you don't have the installation disc, you can probably download the driver and configuration utility from the monitor manufacturer's support website.
  • Touch-screen interfaces work best in applications with big menu buttons or links. For applications that require a lot of cursor or tracking precision, using a mouse is a better option.


Photo Credits

  • Jupiterimages/Comstock/Getty Images

About the Author

Jeff Grundy has been writing computer-related articles and tutorials since 1995. Since that time, Grundy has written many guides to using various applications that are published on numerous how-to and tutorial sites. Born and raised in South Georgia, Grundy holds a Master of Science degree in mathematics from the Georgia Institute of Technology.

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