Using a USB-Serial Converter

October 30th, 2006

From Monitor, an e-mail newsletter published by Windmill Software.

Many laboratory instruments can send data to a computer over RS232 links. As USB ports are replacing RS232 ports on computers, people are increasingly using a USB-Serial converter to access data from their instruments.

The converters are simple to use. You plug the converter into the PC’s USB port and install its driver software. The USB converter will be assigned a COM port. You can check this by opening Windows Control Panel and choosing first System then Device Manager then Ports.

When using a USB-Serial converter, you need to make sure that it is providing data in the way expected by your data acquisition software. The serial communications settings must be the same.

For instance, if you have set your DAQ software to continually acquire data you must make sure that your USB-to-Serial converter is continually providing data, and not buffering it. How you do this depends on your converter. For an Edgeport converter, for example, you need to use its utility program to set its ports for “low latency” and “fast read and writes”.

Entry Filed under: Data Acquisition