TIME/LTIME Constant

You can use ‎TIME‎ constants to operate the standard timer modules. The constant has a size of 32 bits and a resolution in milliseconds.

In addition, the time constant ‎LTIME‎ is available as a time basis for high-resolution timers. The ‎LTIME‎ constant has a dimension of 64 bits and a resolution in nanoseconds.

TIME constant

Syntax

<time keyword> # <length of time>

<time keyword> : TIME | time | T | t
<length of time> : ( <number of days>d )? ( <number of hours>h )? ( <number of minutes>m )? ( <number of seconds>s )? (<number of milliseconds>ms)? // ( ...)? Optional

The order of time units must not be changed. However, it is not required to specify all units. It is permitted to specify the units in uppercase.

Time units

‎D | d‎: Days
‎H | h‎: Hours
‎M | m‎: Minutes
‎s | s‎: Seconds
‎MS | ms‎: Milliseconds

Examples

Correct time constants of an ST assignment

VAR
	timLength : TIME := T#14ms;
	timLength1 : TIME := T#100s12ms; // Overflow in the highest unit is allowed.
	timLength2 : TIME := T#12h34m15s;
	timCompare : TIME;
	xIsOK: BOOL;

	timLongest := T#49D17H2M47S295MS; // 4294967295
END_VAR

IF timLength < T#15MS THEN
	IF timCompare < timLength1 THEN 
		xIsOK := TRUE;
	END_IF;
END_IF

Table 427: Incorrect usage:
`‎timIncorrect := t#5m68s;‎`	Overflow at a lower position
`‎timIncorrect1 := 15ms;‎`	Time marker `‎T#‎` missing
`‎timIncorrect2 := t#4ms13d;‎`	Incorrect order of time units

LTIME constant

Syntax

<long time keyword> # <length of high resolution time>

<long time keyword> : LTIME | ltime
<length of high resolution time> : <length of time> ( <number of microseconds>us )?  ( <number of nanoseconds>ns )? // ( ...)? Optional

You can use the same units for ‎LTIME‎ constants as for ‎TIME‎ constants. You can also specify microseconds and nanoseconds because the specified time is calculated in higher time resolution. ‎LTIME‎ literals are treated internally as data type ‎LWORD‎ and therefore the value resolved in nanoseconds.

Additional time units

‎US | us‎: Microseconds
‎NS | ns‎: Nanoseconds

Examples of correct usage of an ST assignment:

PROGRAM PLC_PRG
VAR
	ltimLength := LTIME#1000d15h23m12s34ms2us44ns;
	ltimLength1 := LTIME#3445343m3424732874823ns;
END_VAR