Abstract: A method by which random bytes are generated. Such a random byte is obtained by adding a prime number once or several times to an 8-bit character. The choice whether a prime number is added once or several times to the 8-bit character depends on whether the preceding addition produced a result larger than or less than 256. The character obtained (modulo 256) also provides the following 8-bit character. A sequence of bits consisting of several bytes is assembled from random bytes thus generated, each byte being generated on the basis of a different prime number.

Abstract: Arthmetic unit for transferring the information at one bit of an accumulator or one of general registers into another bit. The accumulator comprises a first memory circuit while a flag register is used as a second memory circuit. Selection circuits for selecting the data at each bit of the first and second memory circuits are provided. When a given instruction is such that the data stored in the second memory circuit is transferred into a specified bit of the first memory circuit, only the selection circuit corresponding to the specified bit is selected so that the data stored in the second memory circuit is written, whereby the data stored in the second memory circuit is written or transferred into the specified bit of the first memory circuit.