Converters between the serial line (COM port) and other data communication lines.
Serial RS232 port, also known as a COM port, serial line or RS-232 is one of the oldest computer interface. It can be found in many industrial and consumer devices. Until recently, the serial port is equipped with a RS232 in most desktops and on laptops.
It was originally used for modem connection - therefore contains a total of 9 signals. Most devices today, but you only need a three: RxD, TxD and GND (two lines of data and power down).
The downside is a short RS232 maximum cable length - according to only 15 meters (renewable), low noise immunity and risk of ground loops (connecting two devices powered from different potentials may be damaged or destroyed equipment).
As a 100% protection against ground loops is galvanically isolated RS232. If you find some of the drawbacks to RS232 serial port, it is appropriate to convert the heavy-duty industrial RS485 or RS422 or the now ubiquitous Ethernet (network).
