The mechanical features of the switching elements guarantee the reliable switching of the daisy chain without contact losses. The switching elements are located in contact positions a21-a22, b4-b5, b6-b7, b8-b9 and b10-b11. The switching elements close the daisy chain when no daughter card is inserted. Therefore, active components or jumpers are not necessary on VME64x backplanes. The switching solution integrates 5 pairs of switching contacts that short the VME interrupt lines when the daughter card is removed, preserving the integrity of the entire system. The har-bus 64S is an addition to the vendor’s 5-row 160-way connector range har-bus 64 and is fully compatible with the har-bus 64 daughter card connectors.