Issue No.10 - October (2007 vol.56)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TC.2007.1067
Decimal arithmetic has been in recent years revived due to the large amount of data in commercial applications. We consider the problem of Multi Operand Parallel Decimal Addition with an approach that uses binary arithmetic, suggested by the adoption of BCD numbers. This involves corrections in order to obtain the BCD result, or a binary to decimal conversion. We adopt the latter approach, particularly efficient for a large number of addends. Conversion requires a relatively small area and can afford fast operation. The BD conversion, moreover, allows an easy alignment of the sums of adjacent columns. We treat the design of BCD digit adders using fast carry free adders and the conversion problem through a known parallel scheme using elementary conversion cells. Spreadsheets have been developed for adding several BCD digits and for simulating the binary to decimal conversion as design tool.
Computer arithmetic, decimal arithmetic, multioperand adders, hardware design
Luigi Dadda, "Multioperand Parallel Decimal Adder: A Mixed Binary and BCD Approach", IEEE Transactions on Computers, vol.56, no. 10, pp. 1320-1328, October 2007, doi:10.1109/TC.2007.1067