Step 4: Linking the axes to PLCopen FBs

The axis reference g_array_axis_ref[0] which links to the first axis in the system is applied to all PLCopen FBs..

Interfacing the first axis in the system to PLCopen FBs via g_array_axis_ref[0]
Interfacing the first axis in the system to PLCopen FBs via g_array_axis_ref[0]