摘要:
A circuit for controlling the access to at least one area of a memory accessible by a program execution unit, including a first instruction address input; at least one second data address input, the addresses coming from the execution unit; at least one function of correlation of these addresses; and at least one output of a bit for validating the fulfilling of conditions set by the correlation function.
摘要:
A circuit for controlling the access to at least one area of a memory accessible by a program execution unit, including a first instruction address input; at least one second data address input, the addresses coming from the execution unit; at least one function of correlation of these addresses; and at least one output of a bit for validating the fulfilling of conditions set by the correlation function.
摘要:
A method and a system of sharing of a clock by an electronic circuit between at least one first task clocked by at least one first counter and at least one second task clocked by a second counter, the two counters varying at the rate of said clock, the content of the first counter plus or minus an offset value being, on each execution of the second task, assigned to the second counter.
摘要:
A method ciphers a standardized stream of compressed audio or video data, wherein at least one part of the bits of data packets delimited by two consecutive synchronization markers is ciphered by pseudo-random stream.
摘要:
A method ciphers a standardized stream of compressed audio or video data, wherein at least one part of the bits of data packets delimited by two consecutive synchronization markers is ciphered by pseudo-random stream.
摘要:
An electronic circuit comprising a first counter clocked by a clock signal provided to have a first period and provided by an oscillator external to the circuit, and comprising a second counter clocked with a second period by an oscillator internal to the circuit, the second counter being reset each time the content of the first counter is a multiple of a first predetermined value, and a means for activating an alert signal when the second counter reaches a second predetermined value such that the product of the second predetermined value by the second period is greater than the product of the first predetermined value by the first period.
摘要:
A method for loading a program, contained in at least a first memory, into a second memory accessible by an execution unit, in which the program is in a cyphered form in the first memory, a circuit for controlling the access to the second memory is configured from program initialization data, instructions of the program, and at least initialization data being decyphered to be transferred into the second memory after configuration of the circuit.
摘要:
A method for transmitting data between a first and a second point comprises the steps of transmitting data, from the first to the second point, together with a signature comprising bits of a first authentication code, and transmitting an acknowledgement, from the second to the first point. The length of the first authentication code is greater than the length of the signature and the first authentication code comprises hidden authentication bits. The acknowledgement is produced by using hidden authentication bits of a second authentication code presumed to be identical to the first, produced at the second point.
摘要:
A method for loading a program, contained in at least a first memory, into a second memory accessible by an execution unit, in which the program is in a cyphered form in the first memory, a circuit for controlling the access to the second memory is configured from program initialization data, instructions of the program, and at least initialization data being decyphered to be transferred into the second memory after configuration of the circuit.
摘要:
A method for transmitting data between a first and a second point comprises the steps of transmitting data, from the first to the second point, together with a signature comprising bits of a first authentication code, and transmitting an acknowledgement, from the second to the first point. The length of the first authentication code is greater than the length of the signature and the first authentication code comprises hidden authentication bits. The acknowledgement is produced by using hidden authentication bits of a second authentication code presumed to be identical to the first, produced at the second point.