Decoder for a pay television system

Abstract

Abstract The decoder comprises a microprocessor (11) connected to a teletext data receiver (10) and to a generator (14) of text for the television screen. Furthermore, a so-called CPTV card (12) is associated with the microprocessor (11), this card managing the credit required for purchasing broadcasts, storing the purchased broadcasts and enabling the unscrambling of the purchased broadcasts by transmitting to the microprocessor from the point of entry in the sequence which it calculates using information which it has stored as well as that which it receives from the decoder. The broadcast programmes provided are transmitted by the main station and stored in the microprocessor (11). Another memory of the latter stores handling instructions to be effected in order to select a broadcast and purchase it, as well as in order to reload the CPTV card with credit. A keyboard (13) makes it possible to select and view on the television screen the broadcasts provided as well as the handling instructions. This greatly facilitates dialogue between the user and the decoder and contributes to the avoidance of handling errors. The decoder according to the invention operates as a guide to the user for all the operations to be effected. <IMAGE>

Inventors

• 👤 André Kudelski
• 👤 Laurent Laffely
• 👤 Marco Sasselli

Bibliographic Details