Add Serial or Parallel Ports to Your Laptop or Notebook

PC cards, also known as PCMCIA cards, are a popular choice for mobile applications such as field service, whether the field is the factory floor or a real field, outdoors and miles from home. PC cards slip into the slot present on most notebook and laptop PCs and provide from one to four serial ports. With the serial or parallel data port this provides, the laptop can assume almost all the capabilities of a desktop PC.

B&B Electronics Mfg. Co. has a number of different PC cards in their current catalog. They provide one to four RS-232 or RS-422/485 ports from a laptop. The RS-232 serial output is popular as an economical and almost universal protocol for general data communications. RS-422 and RS-485 provide added range, up to 4,000 feet, and RS-485 also allows multi-drop networking with up to 32 nodes.

When used on an RS-485 system, the RS-422/485 PC cards provide automatic Send Data Control. This is a good feature to have, as it eliminates the need for any software based drivers. SDC senses when data flow starts and automatically enables the driver, automatically disabling it when the data flow ends.

PCMCIA serial cards can operate at up to 921.6 kbps. A parallel port version that runs at up to 700 kbps is also available. Output connectors are DB9 on the serial PC cards and DB25 on the


parallel version. Ruggedized versions of the single and dual port serial cards are available.

PCMCIA cards in the B&B Electronics catalog range from about $120 for a single port RS-232 model to about $320 for a 4-port RS-422/485 version. For a full color catalog, phone 815-433-5100 or visit www.bb-elec.com.

Romeltea Media

Information Technology & World News Updated at: 11:10 PM