This application note shows how a Xilinx CoolRunnerTM-II CPLD can be used as a simple logical switch that can quickly and reliably select between different MPEG video sources. The source code for the design is available on the Xilinx website, and is linked from the “VHDL Code” section. The code can be expanded by the user to perform additional operations using the remaining CPLD resources.
As consumer electronics become more complex, we are seeing a significant increase in the number of formats used to transfer data. Video and audio both come in a multitude of different formats, and often from different sources. Managing this data and ensuring the right data arrives at the right destination at the right time is a challenge.
In our example, we use a CoolRunner-II CPLD to select between three MPEG-2 video sources; these could be Satellite, Cable and Terrestrial television. The selected data source can then be sent to a decoder to be streamed to a display, stored on a Hard Disk Drive (HDD), as would happen in a Digital Video Recorder (DVR), or sent over a serial link to another piece of equipment.