1 to 4 PXIe mapping
With switches SW3 and SW4 in the off position, cartridge 1 is connected to all four of the PXIe slots, and the remaining three cartridges are not connected to any of the PXIe slots. This is defined as 1 to 4 mapping, as all four PXIe slots are connected to one cartridge.
For more information about PXIe slot numbers, see Rear panel components.