Abstract:
The invention relates to a method for modular multiplication of a multiplicand (C) with a multiplicator (M) using a module (N), whereby firstly l multiplication shift values are determined (10), using a multiplication forecast method using l blocks of adjacent multiplicator (M) positions. l Reduction shift values are then determined (13), using a reduction prediction method for the l blocks of multiplicator (M) positions. An intermediate result (Z), from a previous iteration step, the module (N), or a value derived from the module and the multiplicand (C) are processed (16) with the l multiplication shift values and the l reduction shift values to obtain the 2l+1 operands (17). The 2l+1 operands are combined by means of a multi-operand summator (18), to obtain an updated intermediate result (Z') for an iteration step, following the previous iteration step, whereby the iteration is continued until all the multiplicator positions (M) are used. Depending on the number of operands the number of cycles to be calculated may be reduced such that a more rapid calculation of the modular multiplication is possible without an increased hardware complexity.
Abstract:
The invention relates to a microprocessor arrangement comprising a data bus (4) for transmitting data between functional units (1, 2, 3). Each unit contains an encoding/decoding device (11, 21, 31) on the bus side. Said devices are controlled by a random-check generator (6) in a synchronous manner. The arrangement allows for a relatively high security against bugging the data which is transmitted by means of the data bus, whereby additional switching requirements are justifiable.
Abstract:
The invention relates to a device for converting a dual rail input having two effective operand bits and two auxiliary operand bits into a one-hot coded output with three output operands. The device comprises a control device for operating said device in data mode and for operating the device in a preparation mode following said data mode. The device also comprises a logic circuit for combining the two effective operand bits and the two auxiliary operand bits so that two of the three output operands have a value differing from that of the third output operand in the data mode. The device is further configured in such a way as to bring all three output operands to the same value in the preparation mode. The conversion device can be used preferably in a three operand adder as interface between a dual-rail three bit half-adder and a sum-carry stage of a two-bit complete adder in order to achieve the same reliability as in three operand adder fully configured in dual-rail technology despite the fact that the two-bit complete adder is configured in single-rail technology.
Abstract:
The invention relates to a register cell which comprises a first input (10) for a data unit to be written into said register cell. The register cell further comprises a second input (12) for a negated data unit to be written into the register cell. A first pair (14) of cross-coupled inverters (14a, 14b) can be coupled with the first input (10) as the first memory circuit. A second pair of cross-coupled inverters (16a, 16b) can be coupled with the second input (12) as the second memory circuit. The use of two cross-coupled pairs of inverters allows to initialize (30) the first input (10) and the second input (12) of the register either at a high voltage status (precharge) or at a low voltage status (discharge) in such a manner as to render the power consumption of the register cell from one cycle to the next more uniform.
Abstract:
Disclosed is a processor comprising a source register (10) with a content, a destination register (12), an arithmetic unit (14) doing a calculation by using the content of the source register, said calculation being done in several cycles and only a portion of the content of the source register being usable in each cycle, a data bus (18) which is connected to the source register (10), the destination register (12), and the arithmetic unit (14), and a processor control unit which is operable so as to feed the content of the source register in portions to the arithmetic unit and the destination register via the data bus during the calculation process such that the content of the source register is written in the destination register once the calculation is done. The inventive processor makes it possible to copy a register for long operands that are to be processed portion by portion from a source register to a destination register via a limited data bus without using any additional machine cycles.
Abstract:
The invention relates to a microprocessor circuit for organising access to data or programmes that have been stored in a memory. Said circuit comprises at least one microprocessor, a memory for an operating system and at least one memory for free programming using individual external programmes. The memory used for free programming has several memory areas containing corresponding address spaces, a qualifier being assigned to each address space. The microprocessor circuit also has means, which prior to the respective addressing of a memory area, load each qualifier assigned to a respective memory area into a first auxiliary register and load the qualifier of the addressed memory area into a second auxiliary register and which then compare the first and second auxiliary registers. At least one bit sequence containing access authorisations is also assigned to each address space of a memory area, which allows code commands and sensitive data to be protected from write access emanating from external programmes.
Abstract:
The invention relates to a data carrier comprising a non-volatile electronic memory (2) for receiving large amounts of data and a microcontroller (3) which is suitable for carrying out cryptographic operations, whereby access to the memory (2) is only possible via the microcontroller (3). Said inventive data carrier is characterised in that an authentication of the user with respect to a data source takes place before data is stored in the memory (2) using said microcontroller (3).
Abstract:
The inventive circuit arrangement for voltage adjustment comprises a longitudinal adjuster (1) provided with an adjustment amplifier (5) and a charging pump (6) located downstream therefrom. The circuit arrangement also comprises a reference voltage unit (4) which is used to produce a reference voltage (S1) for the adjustment amplifier (5) and a starter unit (3) which is used to produce a starter voltage (UOUT) in order to supply voltage to the adjustment amplifier (5), charging pump (6) and reference voltage unit (4) when the longitudinal adjuster (1) is started.
Abstract:
The device for calculation of a multiplication of a multiplier and a multiplicand consists of a device (40) for performing an exact three operand addition in addition to a device(412) for performing an approximated operand addition, and a device (417) for calculating look-ahead parameters using an approximated intermediate result (414) calculated by the device (412). The device for performing the exact three operand addition is also configured in such a way that it can carry out an exact three-operand addition (400') in a current iteration step using the exact intermediate result for the current iteration step and using the look-ahead parameters, calculated by the device (417), for the current iteration step. As a result, the long-number calculator can continuously perform three operand additions and is no longer required to lie idle while look-ahead parameters are calculated. This results in a significant increase in performance when cryptographic calculations are performed.
Abstract:
The invention relates to a half-adder for adding bits of at least two input operands in order to obtain at least two output bits. The inventive half-adder comprised an input stage (10), a plurality of commutation stages (12a, 12b, 12c) and an output stage (14a, 14b, 14c) arranged after each commutation stage, respectively. In a data mode, the commutation stages can operate either for delivering a bit or an inverse bit of an output (18a, 18b, 18c) on the output stage arranged after the corresponding commutation stage. The output stage modifies an output bit with respect to the past preparation mode on the basis of the bit contained in the corresponding commutation stage and completes a complementary bit from the past preparation mode. The half-adder circuit has a surface effectiveness using complete dual-rail logic and being protected against any cryptographic attack.