Applies To:
  • CitectSCADA 1.00, 1.01, 1.10, 1.11, 2.00, 2.01

If a digital array is not declared on a 16 bit boundary, Citect will round it down to the nearest 16 bit boundary. The effect of this is all the offsets in the array will also be changed. For example if you declared an array Test to start at bit 35, Citect will start the array at bit 32. So the index to the array will also start from bit 32 so, Test[0] will refer to bit 32 not 35.

This problem also exists in disk and memory based PLCs. 

Start all PLC digital arrays on 16 bit boundaries.