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Download SPRU131 - Texas Instruments
Transcript
Accumulators A and B FIRS multiplies accumulator A(32–16) with a program-memory value addressed by a program-memory address and adds the result to the value in accumulator B. At the same time, it adds the memory operands Xmem and Ymem, shifts the result left 16 bits, and loads this value into accumulator A. In the LMS instruction, accumulator B stores the interim results of the input sequence convolution and filter coefficients; accumulator A updates the filter coefficients. Accumulator A can also be used as an input for MAC, which contributes to single-cycle execution of instructions with parallel operations. The SQDST instruction computes the square of the distance between two vectors. Accumulator A(32–16) is squared and the product is added to accumulator B. The result is stored in accumulator B. At the same time, Ymem is subtracted from Xmem and the difference is stored in accumulator A. The value that is squared is the value of the accumulator before the subtraction, Ymem – Xmem, is executed. 4-16 Central Processing Unit SPRU131G
