F_SwapRealEx

The way in which a REAL number is represented in the memory of a bus controller (165) is different from the way a REAL number is represented in the memory of an Intel system (PC).
In order to represent a bus controller's REAL number correctly in a PC, it is necessary for the high and low words of the REAL number to be swapped. Under the programming environment this is already done in online or simulation mode. If it is desired to request the REAL data from a bus controller over the network (ADS protocol, ADSDLL, AdsOcx etc.) and to display it correctly in an Intel PC, then it is necessary to convert the REAL data into the correct format. This may take place on the bus controller side or the PC side.

The function F_SwapReal can be used to convert the REAL variables (e.g. variables to be read by a VB application or recorded with TwinCAT Scope View) into a suitable format on the PC side. The function changes the memory representation of the transferred fVal parameter (VAR_IN_OUT).

FUNCTION F_SwapRealEx : BOOL

VAR_IN_OUT
    fVal    :REAL;
END_VAR