Abstract: A demultiplexer for selectively demultiplexing ATM signals and MPEG signals received at an input of the demultiplexer, the demultiplexer comprising an MPEG demultiplexer for demultiplexing an MPEG transport stream, an ATM section for identifying MPEG transport stream data in an ATM signal, and a selection unit for selectively connecting the input to the MPEG demultiplexer or the ATM section according to whether the received signal is an MPEG signal or an ATM signal, wherein the demultiplexer comprises a memory shared between the demultiplexer and the ATM section and the ATM section processes ATM signals by storing the received signals in the memory and providing the MPEG demultiplexer with addresses appropriate for the MPEG demultiplexer to retrieve demultiplexed data from the memory.

Abstract: A demultiplexer for selectively demultiplexing ATM type signals and MPEG type signals received at an input of the demultiplexer, the demultiplexer comprising an MPEG demultiplexer for demultiplexing an MPEG transport stream, an ATM section for identifying MPEG transport stream data in an ATM type signal, and means for selectively connecting the input to the MPEG demultiplexer or the ATM section according to whether the received signal is an MPEG type signal or an ATM type signal, wherein the demultiplexer comprises a memory shared between the demultiplexer and the ATM section and the ATM section processes ATM type signals by storing the received signals in the memory and providing the MPEG demultiplexer with addresses appropriate for the MPEG demultiplexer to retrieve demultiplexed data from the memory.

Abstract: An integrated circuit for use in a digital set top box including at least one control unit, a plurality of data processing units and common data bus for connecting at least two of the processing units to a common external memory wherein two or more common data buses may be provided for the plurality of data processing units and, where there are a plurality of control units, a separate control bus may be provided connecting the control units.