Serial I/O – Just as Useful Today

August 1, 2013

With many things, newer doesn’t necessarily mean better. Automobiles are a good example. Porsche remains the measuring stick in sports cars, yet the design of today’s 911 is amazingly similar to 911s from 30 years ago. Likewise, Serial I/O has evolved over time, but the basic functionality and usefulness remain the same.

Recently, Martin Rowe wrote about the longevity of serial I/O in his blog The Serial Port: It Just Keeps Going. At Sealevel, we couldn’t agree more. In fact, compared to 25 years ago there are more options for implementing serial I/O than ever before. Taking a quick look shows the flexibility afforded today for implementing serial connectivity:

  • PCI and PCI Express boards. Most PCs still support adding I/O via internal expansion slots. Since the serial ports are connected directly to the processor’s bus, adding a serial board to the backplane can still be the best choice, especially in applications that are throughput intensive or require interrupts.
  • USB Serial Adapters. As Mr. Rowe points out in his blog, external adapters offer an easy way to add serial ports to a laptop or any other computer without expansion slots. The simplicity and reliability of adding serial ports using an external USB serial adapter also eliminate the concern of I/O board compatibility with frequently changing PC models.
  • Ethernet Serial Servers. Sometimes the host PC and serial peripherals to be connected are located some distance apart. Using COM Port emulation software on the host, serial ports can be located anywhere on an Ethernet network and accessed remotely from Ethernet Serial Server products.

Serial I/O is a dependable standard and offers flexibility and reliability that make it applicable to a variety of applications and vertical markets. Don’t count on that changing any time soon. At Sealevel, we are constantly improving on what works and some of our best ideas come from our customers. Tell us how we can improve Serial I/O to make it more useful to your application. Email your idea to