1. A method for reconfiguring a parallel configuration of identical functional units in response to a failure of one of said units, said configuration comprising a rightmost unit serving as a spare, at least two input busses coupled to each of said units except for a leftmost and said rightmost units, and at least two output busses coupled to each of said units except for said leftmost and rightmost units, each of said input and output busses suitably coupled to at least two functional units, the method comprising the steps of: shifting the contents of the failed unit and the contents of all the units to the right of said failed unit one unit to the right; deactivating the outputs associated with said failed unit; activating the rightmost input bus associated with each unit for all of the units to the left of said failed unit; activating the leftmost input bus associated with each unit for all the units to the right of said failed unit; activating the rightmost output bus associated with each unit for all of the units to the left of said failed unit and activating the leftmost output bus associated with each unit for all of the units to the right of said failed unit; whereby said failed unit is operationally eliminated from said parallel configuration of identical functional units.