USB to Serial Converters

MEV's fast USB to serial converters provide legacy RS232 or RS485 serial communication interfaces to computers with USB support.

USB232 high speed USB RS232 interface. www.usb232.com
USB485i opto-isolated USB RS485 interface. www.usb485.com
CUSTOM Custom USB Interface?

Many modern Desktop and Laptop PCs do not have serial ports as standard but all have USB ports. The USB232 /485 range provide a compact and cost effective solution to interfacing new PCs to existing RS-232 and RS-485 networks.

The devices are USB 1.1 specification full speed (12 mbits/second) compliant. This means they will work when attached to USB 1.1 or USB 2.0 ports.

Each of the USB232 /485 series of interfaces comes with Windows and Mac OS compatible drivers and are designed to meet stringent performance requirements and be easy to use while maintaining compatibility with standard serial communications boards. The devices are also supported by Linux, FreeBSD and OpenBSD. The Windows drivers are compatible with LabVIEW standard serial driver interface (NI VISA).

USB232 - USB to RS232 Serial Converter

USB232 - USB to RS232 Serial Converter

USB232 high speed USB RS232 interface.

USB232 manual

  • Interface new PCs and laptops to existing RS232 devices and networks
  • Powered from the USB port - no external power supply required
  • Compatible with standard serial communications boards
  • Windows 98/ME/2000/XP drivers
  • Mac OS-8/9/X drivers
  • Windows CE.NET (4.2 or later) drivers for x86 and ARM/XScale processors (USB host controller required)
  • Native support in Linux kernel 2.4 and 2.6 (using 'ftdi_sio' driver)
  • Native support in OpenBSD 3.2 and later and FreeBSD 4.8 and later (using 'uftdi' driver)
  • Support for non-standard baud rates
  • Fast USB to RS232 with data rates up to 1M baud
  • FIFO modes supporting a 384 character receive buffer and 128 byte transmit buffers.
  • Industry standard 9 way connectors
  • Full specification signal levels
  • Implementation of all RS-232 primary control lines
  • Low power consumption
  • RoHS compliant

The MEV USB232 high speed USB RS232 Serial Interface supports faster communication and a wider range of non-standard baud rates than many competing products. This makes them ideal for use with RS232 protocols such as Digital Music Express (DMX), www.dmxmusic.com.

They support baud rates up to 1 MBaud see Supported Baud Rates for USB232U and USB485Ui.

To order USB serial converters please: Buy USB232 USB to RS232 Converter
or e-mail: Pat Marsh
For more information please e-mail: Dave Cooper

USB485i - USB to RS485 Serial Converters

USB485i - USB to RS485 Serial Converter

USB485i opto-isolated USB RS485 interface.

USB485i manual

  • Interface new PCs and laptops to existing RS485 or RS422 networks
  • USB Bus Powered - no external power supply required
  • Compatible with many standard serial communications boards
  • Full optical isolation on USB485i
  • Two wire, half duplex communications without RS485 transmitter enable control from application program
  • Windows 98/ME/2000/XP drivers
  • Mac OS-8/9/X drivers
  • Windows CE.NET (4.2 or later) drivers for x86 and ARM/XScale processors (USB host controller required)
  • Native support in Linux kernel 2.4 and 2.6 ('ftdi_sio' driver)
  • Native support in OpenBSD 3.2 and later and FreeBSD 4.8 and later ('uftdi' driver)
  • Support for non-standard baud rates
  • Fast USB to RS485 with data rates up to 3M baud
  • FIFO modes supporting a 384 character receive buffer and 128 byte transmit buffers.
  • Three point isolated serial communications on isolated versions
  • Industry standard 9 way connectors
  • RS485 Full Duplex, Half Duplex, Multi-drop applications
  • RS485 transmitter enabled automatically in Half Duplex mode
  • Full specification signal levels
  • Low power consumption
  • RoHS compliant

The RS485 converters have big advantages over traditional methods of accessing RS485 networks from PCs. The converters take their power from the USB port and therefore require no external power supply, a big advantage in portable and industrial applications.

The USB485i is fully opto-isolated giving valuable protection to the PC in harsh environments.

They are ideal for use with RS485 two wire networks as another big advantage of the USB485 is that it automatically enables the RS485 transmitter when data is to be transmitted. This allows it to support two wire, half duplex communications without any need to control the RS485 transmitter enable from the application program. In short an application program written to support RS232 comms with no flow control can be made to interface to RS485 without modification.

For information on the range of baud rates supported see Supported Baud Rates for USB232U and USB485Ui.

To order USB serial converters please: Buy USB232 USB to RS232 Converter
or e-mail: Pat Marsh
For more information please e-mail: Dave Cooper

Custom USB Design

If you have your own device that has a serial interface then MEV can design an alternative USB interface for that device. See our USB Design Page.