Patent ID: 7549059

Claim:
Apparatus for processing data, said apparatus comprising: a data source operable to supply a data value to be processed; a destination operable to receive said data value; and a data bus operable to transfer a representation of said data value between said data source and said destination; wherein one or more representation specifying bits are associated with said data value transferred on said data bus, said one or more representation specifying bits specifying which of a plurality of different representations of said data value is used to transfer said data value via said data bus between said data source and said destination, and wherein said one or more representation specifying bits accompany said data value transferred on said data bus and said one or more representation specifying bits are a complement bit specifying whether said data value is represented in a true form or a complement form, and wherein said apparatus is one of: a smart card; a cryptographic device; and a secure device.