Texas Instruments Corporation

Alain Boyadjian

Gilbert Laurenti

Jean-Pierre Giacalone

Francois Theodorou

Yves Masse

Douglas E Deao

Mark L Buser

Marc Couvrat

Shigeshi Abiko

Eric L Badi

Armelle Laine

Herve Catan

Karim Djafarian

Vincent Gillet

Gael Clave

Anne Lombardot

Jean-Marc Philippe Bachot

Eric Ponsot

Jack Rosenzweig

Jean-Louis Tardieux

Walter A Jackson

Laurent Ichard

Emmanuel Ego

Frederic Nidegger

David Russell

N M Ganesh

A processing engine, such as a digital signal processor, includes an execution mechanism, a repeat count register and a repeat count index register. The execution mechanism is operable for a repeat instruction to initialize the repeat count index register with the content of the repeat count register, and to modify the content of the repeat count register. The repeat instruction comprises two parts, the first of which initializes the repeat count index register and initiates repeat of a subsequent instruction, and the second part of which modifies the content of the repeat count register.

Processor with a computer repeat instruction

A processor ( ) is provided that is a programmable fixed point digital signal processor (DSP) with variable instruction length, offering both high code density and easy programming. Architecture and instruction set are optimized for low power consumption and high efficiency execution of DSP algorithms, such as for wireless telephones, as well as pure control tasks. The processor includes an instruction buffer unit ( ), a program flow control unit ( ), an address/data flow unit ( ), a data computation unit ( ), and multiple interconnecting busses. Dual multiply-accumulate blocks improve processing performance. A memory interface unit ( ) provides parallel access to data and instruction memories. The instruction buffer is operable to buffer single and compound instructions pending execution thereof. A decode mechanism is configured to decode instructions from the instruction buffer. The use of compound instructions enables effective use of the bandwidth available within the processor. A soft dual memory instruction can be compiled from separate first and second programmed memory instructions. Instructions can be conditionally executed or repeatedly executed. Bit field processing and various addressing modes, such as circular buffer addressing, further support execution of DSP algorithms. The processor includes a multistage execution pipeline with pipeline protection features. Various functional modules can be separately powered down to conserve power. The processor includes emulation and code debugging facilities with support for cache analysis.

Microprocessors

A multiply-accumulate (MAC) unit, having a first binary operand X, a second binary operand Y, a third binary operand, Booth recode logic for generating a plurality of partial products from said first and second operands, a Wallace tree adder for reducing the partial products and for selectively arithmetically combining the reduced partial products with said third operand, a final adder for generating a final sum, and a saturation circuitry for selectively rounding or saturating said final sum is provided. A dual MAC unit is also provided.

Multiplier accumulator circuits

Growing community of inventors

Vallauris, France

Alain Boyadjian