IEC 61131-3 Function Block Reference Library

Starts timing on rising edge, output activates after preset delay.

Output stays TRUE for preset time after input goes FALSE.

Generates a fixed-duration pulse on rising edge of input.

Timer retains accumulated value when input goes FALSE; requires manual reset.

Siemens retentive on-delay timer that accumulates time across multiple enable cycles.

Retentive on-delay timer with integrated reset input for accumulated time clearing.

Counts up on each rising edge; output activates when count reaches preset.

Counts down from preset value; output activates when count reaches zero.

Counts both up and down with separate done outputs for each direction.

Counter that automatically resets after reaching preset, creating repeating count cycles.

Hardware-accelerated counter for high-frequency pulse inputs beyond normal scan rate.

Set-dominant flip-flop: output latches TRUE on set, cleared by reset. Set wins if both active.

Reset-dominant flip-flop: reset wins if both set and reset are active simultaneously.

Detects FALSE-to-TRUE transition, outputs single-scan pulse on rising edge.

Detects TRUE-to-FALSE transition, outputs single-scan pulse on falling edge.

Returns TRUE when first input is strictly greater than second input.

Returns TRUE when first input is greater than or equal to second input.

Returns TRUE when both inputs are exactly equal.

Returns TRUE when inputs are not equal to each other.

Returns TRUE when first input is less than or equal to second input.

Returns TRUE when first input is strictly less than second input.

Adds two or more numeric values and outputs the sum.

Subtracts second input from first input, outputs the difference.

Multiplies two numeric values and outputs the product.

Divides first input by second input, outputs the quotient.

Returns the remainder after integer division of two values.

Returns the absolute (non-negative) value of the input.

Copies a value from source to destination for any data type.

Reverses byte order of a word value for endianness conversion.

Shifts bits left by N positions, filling right with zeros. Equivalent to multiply by 2^N.

Shifts bits right by N positions. Equivalent to integer division by 2^N.

Rotates bits left; bits shifted out the left wrap around to the right.

Converts 16-bit integer to 32-bit floating-point real value.

Converts 32-bit floating-point value to 16-bit integer with rounding.

Converts FALSE to 0 and TRUE to 1 for numeric operations.

Converts integer value to its decimal string representation for display or logging.

General type conversion framework covering all IEC 61131-3 type conversion functions.

Closed-loop feedback controller using proportional, integral, and derivative terms.

Converts analog percentage to pulsed digital output with proportional duty cycle.

Limits rate of change to create smooth transitions between values.

Clamps a value between minimum and maximum boundaries.

Joins two or more strings into a single combined string.

Extracts a specified number of characters from the beginning of a string.

Extracts a specified number of characters from the end of a string.

Finds position of a substring within a string; returns 0 if not found.

Selects between two values based on a boolean condition: FALSE=IN0, TRUE=IN1.

Selects one of N input values based on an integer selector index.

Returns the larger of two or more input values.

Returns the smaller of two or more input values.

Constrains input value to specified minimum and maximum range.