Abstract: The system is for passing clear DVD program streams from a CPU (central processing unit) to an MPEG-2 decoder. In the system the CPU is connected to a first bus interface. A system memory is connected to the first bus interface via a memory bus. A second bus interface is connected to the first bus interface via a PCI (peripheral component interconnect) bus and a DVD data source is connected to the second bus interface. A packet data decoder is connected to the memory bus via a buffer. The CPU reads DVD data from the DVD data source across the PCI bus, decrypts the DVD data and creates a packet data, and sends the packet data to the buffer via the memory bus. The MPEG-2 decoder receives the packet data, via the transport bus, from the buffer. In more general terms, the system connects two existing busses in a computer of set-top box.