摘要 |
A data shifter is constructed in monolithic integrated-circuit form essentially from three basic cells, namely: a first or A type of bit-slice cell with a multiplexer for selecting one of two inputs to a clocked output latch, a second or B type of bit-slice cell with a multiplexer for selecting one of two inputs to a cascaded pair of clocked latches, and a control cell for controlling the selection process in bit-slice cells arranged in a stack therewith. In addition where the order of the bits in each successive digit of the shifter output needs to be rotated, this can be accomplished using combinations of two further types of basic cells, namely: a braid-slice cell, and a braid-cap cell. These cells are rectangular and tile in a close-packed mosaic. The disclosure describes how to make a same set of basic cells that is adaptable for use both in left shifters and in right shifters.
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