Serial to USB converters are devices that convert the data sent by a serial-enabled device for use by a USB port. The serial end has a DB9 connector, which plugs into the serial device. The USB connector plugs into the computer's USB port or a connected USB hub. Most commonly the USB data signals are converted to either RS232, RS485, RS422, or TTL-level UART serial data. The older serial RS423 protocol is rarely used any more, so USB to RS423 adapters are less common.

• Serial to USB converters continue to use your older serial-enabled device through your new computer's USB por
• Serial to USB converters can be isolated or non-isolated