Technical Spec´s WAN USB *

© Farsite Communication Ltd. • 2012


The FarSync Flex V2 USB adapter is a high quality synchronous / asynchronous solution for business, government and military applications, it has been developed to provide a high performance, neat, durable and versatile connectivity for Linux and Windows systems.

The bus powered USB adapter will support a synchronous line at speeds of up to 2.048 Mbits/s continuous, higher speeds can be supported in bursts. The highly flexible universal network connector supports RS232, X.21, RS530 (RS422 signaling), RS449 , RS485 and V.35 network interfaces.

The adapter can support the host computer's TCP/IP protocol stack or an Application can be written to use the low level API for a variety of different functions. The FarSync Flex SDK provides a Developers Toolkit for the product.

The Flex can be used for line monitoring with the addition of a special Monitor cable. A monitoring application is included. The monitoring support is also compatible with Wireshark.

The FarSync Flex supports PC connections to secure BRENT units using an X.21 connection.

For DAB connections the FarSync Flex supports ETI (NI, V.11) and STI(PI, V.11).

Features under Linux:

The Flex adapter installs seamlessly as a plug and play device under the popular Linux 32 and 64 bit distributions. The 2.0 USB adapter supports Linux kernel version 2.6 in 32 and 64 bit formats, including the leading distributions supplied by Redhat, SuSE, Mandriva, Debian, Ubuntu, Fedora, Slackware and more. SMP (multi-processor) systems are supported.

The low level API is based on the raw socket interface supports HDLC framed and transparent bit stream data.

The Flex adapter can use the TCP/IP stack to allow access to IP based networks such as the Internet.

FarSite is committed to supporting the FarSync Flex on new versions of Linux and Linux kernels as they are released. The source code for the driver is supplied with the product, allowing rebuilding by the end user for use with almost any of the current or future Linux variants.

Features under Windows:

The Windows based API to the entire range of FarSync cards/devices is referred to as the FarSync Windows API (FsWinAPI). This is an extension of the MS COMM API and enables, for example, applications developed to support COM ports, to be easily ported to use FarSync support in synchronous or asynchronous modes. This standardization enables the API to also be readily accessible from higher level environments such as .NET, C#, VB etc.

The FsWinAPI provides applications with direct access to the card's communications port/s for bit sync (HDLC) framing and also transparent bitstream operation for video and voice type applications.

The FarSync Flex can also be installed to appear as a NDIS (LAN) interface so it can simply use the TCP/IP stack over PPP to allow access to IP based networks such as the Internet.

The FarSync Flex installs seamlessly as a plug and play device under Windows 7, Windows XP, Vista, Windows Server 2003 and Windows Server 2008 on both 32 and 64 bit, single and multi-core systems. The FarSync drivers are signed by Microsoft for easy installation.

LabVIEW applications can access this adapter.

Developers Toolkit:

The FarSync SDK provides a Developers Toolkit with full documentation, a bitstream encoding and decoding library, useful utilities such as a line monitor and many sample applications for Linux and Windows.

Typical Applications

The FarSync Flex adapters are suitable for a very wide range of uses. Typical applications include:

        • Internet Access and remote office access over leased lines
        • HDLC framing support for non standard or specialist protocols
        • Connection to secure BRENT units
        • Interfacing video and voice bitstreams such as T-DMB, DAB ETI (N1, V.11) and STI (P1, V.11)
        • Interfacing high speed MPEG Video bitstreams to Servers
        • Line monitoring
        • Data generators for test systems
        • Engineering monitoring and control systems
        • Master or slave in a RS485 half duplex multidrop environment

FarSync Flex - Product Details

The FarSync Flex is supplied with support for Windows and Linux. This includes a low level driver that allows access to the communications features available in the hardware and an optionally installable driver that connects with the standard TCP/IP protocol stack to allow access to IP based networks such as the Internet. Multiple devices can be installed.

Key Features

The intelligent FarSync Flex is designed for reliability, high performance and flexibility. The adapter uses a fast ARM processor with Flash and RAM for the onboard code.

        • Network interfaces for X.21 (V.11), V.35, RS232 (V.24, X.21bis), RS449, RS530 (EIA530, RS422), and RS485.
        • Line speeds of up to 2.048 Mbits/s (E1 Speed)
        • USB 2.0 high-speed mode (480mb/s) and 1.1 compatible
        • Multiple Flex operation from a single server
        • High efficiency USB Bus powered, energy saving design
        • NRZI, NRZ, FM0 and FM1 line signaling formats, tri-state transmitters and receivers
        • Half duplex multidrop for 2 wire (NRZI, FM0 or FM1) RS485 operation
        • Internal and external line clocking with multiple clock selection options
        • Dual bank flash for secure in field upgrades and previous system restore capability
        • Software selectable Synchronous HDLC and Transparent Bitstream formats
        • New releases of the software available for free download from the Download page in this web sites Support section
        • Optional mounting brackets (factory fitted)

Key Features supported on Linux

The FarSync Flex installs seamlessly under Linux kernel series 2.6 on both single and multi-core 32 and 64 bit systems. All the popular distributions are supported including Red Hat, SuSE, Slackware, Ubuntu, Mandriva, Debian and Fedora.

Installation is simple, the driver is dynamically loadable so a kernel rebuild is not required for the driver to be installed. The driver acts as a dynamically loadable module. The link level protocol can be PPP, Cisco HDLC or Frame Relay with optional authentication by CHAP, MSCHAP or PAP (RFC 1334) providing a standard point-to-point network interface. The driver is supplied with source code.

The Raw Sockets API allows applications developed using the FarSync Flex SDK to access the full feature set of the hardware, these include bit synchronous (HDLC framed) data, transparent bitstream data (eg DAB STI, ETI on V.11), asynchronous data and signal modes NRZ, NRZI, FM1 and FM0.

A configuration utility is provided to set the line speed, interface type and protocol, after which the ports may be configured with standard networking tools.

Key Features supported on Windows

The FarSync Flex installs easily under Windows 7, Windows Vista, Windows XP, Windows Server 2003 and Windows Server 2008 on single or multi-core 32 and 64 bit systems. A FsWinAPI driver is installed with the optional installation of an NDIS (LAN) driver. The NDIS driver supports TCP/IP running over PPP with optional authentication by CHAP or PAP (RFC 1334) providing a standard point-to-point network interface. Standard COM port access is provided for use in Async mode.

The drivers are signed by Microsoft for easy installation. Applications running in LabVIEW can access the adapter.

The product is supplied with a comprehensive configuration utility and its own Line Monitor that allows the user to record, display and store line traffic with WAN protocol decoding for fast debugging. The Line Monitor application is also suitable for standalone use with a special cable. The line monitor function is compatible with Wireshark via a DLL supplied with the Flex.

FarSync Flex's enhanced SDCI API allows applications developed using the FarSync Flex SDK to exactly control the type of data sent and received in bit synchronous (HDLC framed) data and transparent bitstream formats (eg DAB STI, ETI on V.11) in signal modes NRZ, NRZI, FM1 and FM0.

FarSync Flex SDK - The Developers Toolkit

The SDK includes support for writing applications on both Linux and Windows and contains documentation, working sample applications, development and test utility applications. There is everything a user needs to rapidly develop and test a wide variety of applications such as specialist synchronous (HDLC framed) protocols or transparent bitstream data requirements including Audio, MPEG Video T-DMB and DAB ETI and STI with bitstream encoder and decoders. Also included are details on using the Flex with RS485 networks.

The FarSync SDK is ordered separately from the FarSync Flex.


For Windows configuration is by a GUI application

The line can be reconfigured and restarted without reloading the software.

There is context sensitive help and an on-line manual should it be required. An advanced tab permits users to exactly specify the configuration of the line if necessary.

For Linux a configuration utility is provided, alternatively text files can be used.

FarSync Flex - Software   Technical Specifications


Distribution Support

Distributions by Red Hat, SuSE, Slackware, Mandriva, Ubuntu, Debian, Fedora and more.
  Drivers for kernel series 2.6 on both single and multi-core 32 and 64 bit systems

Kernel Support

Sub versions of kernel releases from 2.6.12 onward. The products may operate successfully with earlier versions of the kernel but no specific testing has been undertaken by FarSite

Protocol Supported

TCP/IP, PPP, Cisco HDLC, Frame Relay, CHAP, MSCHAP, PAP (RFCs 1661, 1332, 1334)

API and Interfaces

Raw Socket API


O/S Types

Windows 7, Windows XP, Windows Vista, Windows Server 2003, Windows Server 2008, LabVIEW running on a Windows O/S.
32 and 64 bit (single and multi-core systems)

Protocol Supported

TCP/IP, PPP, CHAP, PAP (RFCs 1661, 1332, 1334)

API and Interfaces

FsWinAPI, NDIS (LAN) where the line appears as a LAN interface


Line Monitor to record, display and store line traffic included

* All specifications are subject to change