MSP FX S/O 2-24-Line PCM Interface

The MSP-FX S/O PCM interface is a general-purpose PCM interface for host-based telephony media processing. It allows the BladeWare user to interface with office trunks (FXO), PBX station trunks, and to support fax terminals and analog phone “behind” the system.

The MSP-FX S/O is a half-height PCI or PCI Express board with 2, 4, 6… to 24 ports using one expansion-card slot. Each card has either two or four ports, depending on the number of two-port daughter cards included. The daughter-cards can be either station or office-trunk interfaces in any combination. Expansion beyond four ports is accomplished by interconnecting up to six boards via a micro-backplane connector (as shown below). Additional power for configurations beyond 8 ports or station interfaces require that the host PC’s 12-volt power supply be connected via a standard power cable. Since all 24 ports are part of the same assembly, all ports operate on the same PCM clock.

The board includes codecs with the low-distortion characteristics needed for high-speed modems, such as Commetrex’ V.34 fax modem. The PCM data are buffered and transferred to the host PC via an efficient PCI or PCI Express plug-and-play interface.

The MSP FX S/O is also available with the optional OpenMedia media-processing software environment. OpenMedia is a comprehensive multi-stream software environment that permits the user to efficiently develop host-based signal-processing functions.


  • Supported by BladeWare
  • Intermix FXS and FXO to 24 ports
  • 2U form factor (120 mmx55 mm)
  • Autosense with 5 and 3.3 volt busses
  • PCI 2.2 compliant
  • RJ-11 cables included
  • 32-bit bus master for 132 Mbytes/sec
  • Temp range of 0-50O C
  • Windows and Linux support
  • OpenMedia streams framework


  • Software-defined media
  • Multiple media per board
  • Ultra-low distortion, low-noise data
  • Multiple vendors per board
  • Productive development
  • Improved strategic options
  • Configuration flexibility
  • Broad market coverage
  • Support for high-speed modems
  • Easily develop proprietary media processing technologies

System Overview

The MSP FX S/O is optimized for applications requiring from 2-to-24 analog line interfaces. PCM data are managed by a PGA and transferred between the board and the host computer over a PCI or PCI Express plug-and-play interface.

Analog Trunk Interface

The MSP-FX S/O includes up to 12 two-port daughter cards that provide either station or office trunk interfaces in any combination. The interfaces use the industry-leading Silicon Labs ProSLIC series of interface circuits. Notable features include SiLabs patented capacitive isolation for 5,000 volt isolation on office trunks and an internal ringing power supply that generates 90 volts peak from a single 3.3 or 5 volt supply.

Related Publications

  • MSP-H E/T Product Bulletin
  • MSP BRI Product Bulletin
  • OpenMedia SDK Product Bulletin
  • BladeWare HMP Product Bulletin
  • PowerFax for BladeWare Product Bulletin


Compatibility PCI 2.2 and PCI Express
Warranty Lifetime
PCI Bus 32-bit bus master DMA at 132-Mbytes/sec.
Form factor 2U 120 mm x 55 mm
Initialization PCI Plug-and-Play
Connectors Four, RJ-11 for telco lines per end plate (up to six end plates)
Processor FPGA
Power 0.8 amp peak, 300 MA operational at 3.3 or 5 volts (autosense)
Temp Range 0-50o C
Cables Shipped with RJ11-terminated cables
Trunk Interfaces Two FXS or FXO analog trunks per daughtercard
Operating System Windows and Linux