Applies To:
  • CitectSCADA
  • MHI GETCP driver version

The GETCP driver can return incorrect REAL values from a PLC under the following conditions:

1. The user project is configured with REAL variables on non-aligned and inconsistent boundaries. (For this to be possible the [General]CheckAddressBoundary=0 must be set). In this case the value returned can be either 0.00 or undefined and may not be consistent.
2. The registers in the PLC do not contain a valid bit-pattern for a REAL variable according to the IEEE 754 32 bit floating point representation. In this case the value returned will be 0.00

Citect have confirmed that this is a problem in the GETCP driver. This problem has been fixed in version and later of the GETCP driver.

GETCP 9070 9030 REAL float invalid value