Standard functions

logiccloud provides a library of standard functions that can be called from any Structured Text body. Functions are stateless: they take their inputs, compute a result, and return — there is no instance to declare (unlike function blocks).

This reference is split by category. Each category page lists every function in that group with its signature and a short usage example.

Categories

• Math and arithmetic — ABS, SQRT, trigonometry, ADD/SUB/MUL/DIV, MOD, EXPT, MOVE.
• Bit-string functions — shifts/rotates (SHL, SHR, ROL, ROR) and bitwise logic (AND, OR, XOR, NOT).
• Selection and comparison — SEL, MAX, MIN, LIMIT, MUX, GT, GE, EQ, LE, LT, NE.
• String functions — LEN, LEFT, RIGHT, MID, CONCAT, INSERT, DELETE, REPLACE, FIND.
• Date and time — duration/date arithmetic, CONCAT_*/SPLIT_*, DAY_OF_WEEK, and the SYS_*_DATE_TIME clock extensions.
• Array bounds and validation — LOWER_BOUND, UPPER_BOUND, IS_VALID, IS_VALID_BCD.
• Conversion and endianness — the generated <FROM>_TO_<TO> family (cross-links to the type conversion rules) plus TO_BIG_ENDIAN / TO_LITTLE_ENDIAN / BIG_ENDIAN_TO / LITTLE_ENDIAN_TO.

result := SQRT(area);                  // math
both   := AND(statusA, statusB);       // bit-string
chosen := SEL(useBackup, primary, backup);  // selection
pos    := FIND(line, 'ERROR');         // string
nowUtc := SYS_UTC_DATE_TIME();         // date/time

Generic parameter types

In the category tables the generic parameter types describe the family of concrete types accepted:

Generic type	Accepts
ANY	Any type
ANY_NUM	SINT…ULINT, REAL, LREAL
ANY_REAL	REAL, LREAL
ANY_INT	SINT, INT, DINT, LINT, USINT, UINT, UDINT, ULINT
ANY_BIT	BOOL, BYTE, WORD, DWORD, LWORD
ANY_ELEMENTARY	Any elementary (non-derived) type
ANY_STRING	STRING, WSTRING
ANY_CHARS	STRING, WSTRING, CHAR, WCHAR

Note

A return type shown as ANY_NUM/ANY_REAL/etc. means the result type is resolved from the actual argument types at compile time. Functions marked with IN, … (or “2+ args”) accept a variadic list of at least two inputs.

Type conversion functions

Conversion between data types (e.g. INT_TO_REAL) is provided by a large, rule-generated family of functions documented on the conversion page and, for the naming rules and type set, on the separate type conversion page.

Remote procedure call

Function	Parameters	Returns / outputs
RPC_CALL	TOPIC : STRING, COMMAND : STRING, PARAMS : ANY, TIMEOUT : TIME, FALLBACK_VALUE : ANY, ASYNC : BOOL	returns ANY; out RESULT : INT

RPC_CALL is a logiccloud extension for invoking a remote service (for example a REST-RPC connection) over the platform’s messaging layer. It returns the remote result (typed from FALLBACK_VALUE) and reports an INT status through its RESULT output. See the dedicated RPC_CALL reference for the full signature, sync/async semantics, result-code table and a worked example.