Abstract: A processor formed from a signal processing unit operating according to instructions transmitted by a bus line, including a slave section provided with an address/data port for connection to a master signal processing circuit; a first buffer register in which data coming from the master processing circuit via the address/data port can be written and read in order to be processed by the processing unit, a second buffer register in which the data processed by the processing unit can be written, then read in order to be directed via the address/data port to the master processing circuit and a sequential control circuit so that access to these buffer registers is allocated in turn to the processing unit and to the master processing circuit. A master section is also provided intended to be connected to at least one slave circuit.

Abstract: A data processor for executing a program of instructions stored in a program memory controlled by a program counter. To execute a loop control instruction, calling for repeated execution N times of a sequence of "i" instructions, the processor includes a loop circuit having an instruction counter which counts execution of the instructions in the loop sequence and produces an end-of-sequence signal upon each completion of the loop, a register which refreshes the program counter with the address of the first instruction in the loop in response to each end-of-sequence signal, and a loop counter which counts the number of completions of the loop and delivers a signal indicating the end of the loop portion of the entire program and enabling the program counter to continue on with the rest of the program. The delay in loop execution permits initializing of registers in the data processor so as to permit pipeline execution of the loop instruction.

Abstract: A data processing apparatus in which a memory (10) is accessed at addresses stored in an address regiser (20). An incrementation circuit (38) successively increments or decrements the address stored in the principal register, under the control of an address cycling circuit (22). A pair of auxiliary registers (30, 35) respectively store the minimum and maximum address values to be reached in the principal register, and a comparison circuit (37) determines when the address therein matches the minimum or maximum value. The address cycling circuit, together with the comparison circuit, loads the principal register with the minimum address value when the address therein reaches the maximum value, the address therein thereafter being decremented, and loads it with the maximum address value when the address therein reaches the minimum value, the address therein thereafter being incremented.

Abstract: A processor for carrying out a calculation mode from a selected plurality of different modes. The processor includes a clock pulse generator which generates clock pulses in an order for processing subsequent data. A mode circuit is included for detecting a mode declaration instruction. The mode declaration instruction is decoded to select a different clock pulse cycle for each different mode selected. Mode control signals and the selected clock pulse cycle are applied to a control code and borrow management circuit to enable the arithmetic and logic unit to carry out one or more operations of the mode control signals.