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S7 SCL Reference

SCL Best Practices: Naming Conventions, Structure, and Comments

SCL programming best practices based on the Siemens Programming Guideline. Covers naming conventions, code structure, REGION keyword, commenting, language selection, and common mistakes to avoid.

10 min readSCLbest practicesnaming convention

SCL Mathematics: Arithmetic, Comparison, Logic, and Conversion Operators

Complete SCL operator reference: arithmetic (+, -, *, /, MOD, **), comparison (<, >, =, <>), logic (AND, OR, XOR, NOT), type conversion (INT_TO_REAL, DINT_TO_REAL), and numeric functions (ABS, SQRT, SIN, COS). With precedence rules and data type behavior.

10 min readSCLoperatorsarithmetic

SCL Counter Functions: CTU, CTD, CTUD — Complete Reference

Complete reference for IEC counter function blocks in SCL: CTU (count up), CTD (count down), CTUD (count up/down). Syntax, parameters, examples, and S5 ZV/ZR migration notes.

8 min readSCLcounterCTU

SCL Syntax Reference: IF, CASE, FOR, WHILE, REPEAT

Complete SCL syntax cheat sheet for Siemens TIA Portal. IF/THEN/ELSE, CASE, FOR, WHILE, REPEAT with code examples. For S7-1200 and S7-1500.

8 min readSCLsyntaxIF

SCL Data Types Reference: BOOL, INT, DINT, REAL, STRING, ARRAY, STRUCT

Complete SCL data type reference for Siemens TIA Portal. Elementary types (BOOL, INT, DINT, REAL, STRING), complex types (ARRAY, STRUCT, UDT), value ranges, and memory sizes.

7 min readSCLdata typesBOOL

SCL Timer Functions: TON, TOF, TP, TONR

SCL timer function reference for Siemens TIA Portal. IEC timers TON (on-delay), TOF (off-delay), TP (pulse), TONR (accumulating). Syntax, timing diagrams, and examples.

6 min readSCLtimerTON