FTDI has released two serial interface converter cables that incorporate transceivers to facilitate connecting RS422 or RS485-based peripherals to a PC’s USB port. Using FTDI’s FT232RQ USB to asynchronous serial interface IC, the USB-RS485-WE converter cable includes an RS485 transceiver while the USB-RS422-WE cable utilises an RS422 transceiver. The far end of the 1,8 m cables are unterminated.

With the electronics encapsulated in the USB connector, these cables provide a quick, easy and transparent method of supporting these serial interface standards. With the complete USB protocol being managed within the FT232RQ device, there is no requirement for designers or end-customers to concern themselves with how to implement the USB standard. Additionally, royalty-free device drivers for the FT232RQ are available. Both VCP and D2XX drivers are available for most popular operating systems such as Microsoft Windows, MAC OS X and Linux.

A feature of the FT2232RQ provides a user writeable EEPROM area. This allows the cables’ USB interface to be customised using FTDI’s MPROG utility. The internal EEPROM can be programmed in-circuit over the USB interface without any additional voltage requirements.

The converter cables are suitable for a range of industrial applications such as instrumentation, machine control and data collection.