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Radix-16 Signed-Digit Division
December 1990 (vol. 39 no. 12)
pp. 1424-1433

A two-stage algorithm for fixed point, radix-16 signed-digit division is presented. The algorithm uses two limited precision radix-4 quotient digit selection stages to produce the full radix-16 quotient digit. The algorithm requires a two-digit estimate of the (initial) partial remainder and a three-digit estimate of the divisor to correctly select each successive quotient digit. The normalization of redundant signed-digit numbers requires accommodation of some fuzziness at one end of the range of numeric values that are considered normalized. A set of general equations for determining the ranges of normalized signed-digit numbers is derived. Another set of general equations for determining the precisions of estimates of the divisor and dividend are derived. These two sets of equations permit design tradeoff analyses to be made with respect to the complexity of the model division. The specific case of a two-stage radix-16 signed-digit division is presented. The staged division algorithm used can be extended to other radices as long as the signed-digital number representation used has certain properties.

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Index Terms:
two-stage algorithm; radix-16 signed-digit division; normalization; design tradeoff; digital arithmetic.
Citation:
T.M. Carter, J.E. Robertson, "Radix-16 Signed-Digit Division," IEEE Transactions on Computers, vol. 39, no. 12, pp. 1424-1433, Dec. 1990, doi:10.1109/12.61063
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