GetCurrentLTimeStamp

The issue when getting timestamps: two different base times

The function F_GetSystemTime returns the current time in 100 nanosecond steps as ULINT since 1.1.1601 (Windows base time) The LDATE_AND_TIME type starts on the UNIX base time - 1.1.1970.

To get the correct time in the end, we have to subtract the difference of 369 years or 11644473600 seconds.

• Return type: LDATE_AND_TIME

Parameters

none

Code

Declaration

FUNCTION GetCurrentLTimeStamp : LDATE_AND_TIME
VAR CONSTANT
	(* 369 years in seconds, the difference between UNIX starttime (1970) and windows starttime (1601) *)
	CORRECTION	: ULINT := 11644473600;
END_VAR

Implementation

GetCurrentLTimeStamp := TO_LDT(F_GetSystemTime()*100 - CORRECTION*TO_ULINT(1E9));