Videoconferencing System Development

VTLinx Multimedia Systems 
Multimedia H.323 Video Conferencing Appliance


PTR Group Gets VxWorks Into The Mix, And Team Up To Speed
VTLinx Multimedia Systems, Inc., was a research and development multimedia technology company. Their mission was to offer products and services that help people use voice, video, and data at anytime, from any place, using any enabled device. Their products supported the management and delivery of multimedia over today’s heterogeneous networks, addressing the challenges presented by the large diversity in user display capabilities, user processing power, and network bandwidth. Due to market forces beyond their control they ceased operations in 2002.



The first product offering for VTLinx was a video conferencing solution consisting of a custom system board with custom PCI multimedia cards. This main system board runs VxWorks® on a Motorola MPC8260. The MPC8260 processor communicates with up to 8 custom multimedia cards on two separate PCI buses through a Tundra PowerSpan PCI bridge chip

The PTR Group reduced the risk associated with a complete custom hardware solution by building a testbed made up of COTS components that closely resembled the final hardware design. This allowed VTLinx’s engineers to develop hardware specific code well before the actual hardware was even ready.

In order to get the VTLinx engineering team up to speed with VxWorks® as quickly as possible, The PTR Group created a custom training class that was tailored to the specific needs of the VTLinx engineering staff. This 3-day class covered such things as basic VxWorks® architecture and program flow, inter-task communication, the I/O subsystem, basic networking facilities, and how VxWorks® supports the PCI bus. The students left this class with the basic skills necessary to become productive members of the software and hardware product development team.

The PTR Group was further able to jumpstart the product development effort by integrating the Radvision H.323 stack into the VTLinx software architecture. We then went so far as to modify this H.323 stack to work under the VxWorks simulator. This greatly reduced the development cycle because it allowed the applications engineers to debug and test software while the product hardware was still under development.

The PTR Group was able to reduce the risk associated with designing a completely new product by designing and implementing several of the key architecture components.

One of these key components was the PCI bus software. Because the PCI busses had to support the high data rates associated with several simultaneous multimedia data streams, this software had to be fast, efficient, and rock solid. The PTR Group wrote the driver for the PCI bridge chip, and the PCI bus configuration and enumeration software. We developed software to configure and boot the PCI multimedia cards. We also developed a custom VxWorks PCI interface that was used as the foundation for the communications between the host processor and the multimedia cards.

In addition to our design services, VTLinx was also able to take advantage of our debug experience to help diagnose and solve complex system integration issues. These issues ranged from VxWorks BSP development bugs to low-level design flaws in their custom hardware. In fact, we were so effective at solving problems that we were able to shave months off the debug and integration phase of the project.

One of the things that made our involvement with VTLinx so unique was the fact that we worked together as one team and not two separate organizations. The PTR Group was in the trenches with their engineers, working side-by-side throughout the entire product development cycle. In this way the VTLinx staff was able to learn from our knowledge and methodologies, and acquired the skills necessary to solve future problems on their own.