Interface between a receiver and a sub-system
AssigneeU.S. Philips Corporation
InventorsPeter R. Brennand, Bruce Murray
Life of this patent
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Abstract
An interface arrangement between a television receiver (1) and a conditional access sub-system (3), in particular for MAC type television signals comprises a bus having a first line (CKFH) conveying clock signals at television line frequency, a second line (DATA) conveying data during prescribed periods in a four television frame period bus cycle and a third line (DIRN) conveying a signal indicating the direction of data travel on the second line. The bus may be connected to a number of sub-systems (3(1), 3(2)) internal to the television receiver or may be connected via a connector unit (7) to external sub-systems (5(1), 5( 2)).
Claims5
An interface arrangement between a television receiver and a conditional access sub-system comprising:
- a bus having a first line conveying clock signals at television line frequency rate from said receiver to said sub-system, a second line conveying data with a bit rate corresponding to that of the clock signal rate from said receiver to said sub-system during a first part of a bus cycle period and from said sub-system to said receiver during the remaining part of said bus cycle period, and a third line conveying a direction signal indicating to said sub-system the direction of data travel on said second line, the bus cycle period having a duration equal to four television frame periods, the data on said second line during the first part of each bus cycle period including the unique address of the sub-system with which the receiver is in communication together with data received by said television receiver.
An interface arrangement between a television receiver and a conditional access sub-system, comprising a bus having a first line conveying clock signals at television line frequency rate from said receiver to said sub-system, a second line conveying data with a bit rate corresponding to that of the clock signal rate from said receiver to said sub-system during a first part of a bus cycle period and from said sub-system to said receiver during the remaining part of said bus cycle period, and a third line conveying a direction signal indicating to said sub-system the direction of data travel on said second line, the bus cycle period having a duration equal to a plurality of television frame periods, the data on said second line during the first part of each bus cycle period including the unique address of the sub-system with which the receiver is in communication together with data received by said television receiver.
Dependencies are inferred from the claim text.