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

The support of direct I/O addressing from Citect uses an undocumented AB protocol type. This data type is unreliable as is assumes the position of the I/O in the PLC rack. Because of this, CIT no longer recommends use of this feature. This support will be removed from the documentation in future (but will remain in Citect for existing users). 

Don't use direct I/O addressing. Move data to other registers and read and write to those registers.