FLL — Fill File

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Description

FLL (Fill File) writes one value into Length consecutive elements of an array every scan its rung is true. Use it to zero a buffer at the start of a cycle, preset every element of a recipe to a default, or blank a STRING array. It is an output instruction with no state and no status bits. Do not use FLL for one element; that is a MOV, and a scalar Dest is refused.

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Operands

Operand	Type	Format	Valid Range	Required	Description
Source	A scalar tag, member, element or literal	Tag, 0, "----"	Any resolvable value	Yes	The value written to every element.
Dest	Array tag, or an element of one	Tag, Tag[n]	Numeric or STRING array	Yes	Where the fill starts. An element sets the start offset.
Length	Whole number	6	1 up to the elements left from the offset	Yes	Elements written.

A numeric Source into a STRING array, or the reverse, is refused at validation, as is a Length that runs off the array. The Source is read once, before the loop, so a Dest that contains the Source element cannot change the value part-way through.

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Scan Behavior

Prescan

Nothing.

Rung-condition-in is false

The instruction does nothing. Dest holds.

Rung-condition-in is true

Source is read once and written to each of the Length elements, every scan the rung is true. A REAL Source into a whole-number array truncates toward zero.

Postscan

Nothing.

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Example

Scenario: A six-element measurement buffer is cleared at the start of each batch.

Tags:

• Clear_Buf — Batch start, BOOL
• Buffer — Measurement buffer, INT[6], holding 1, 2, 3, 4, 5, 6 from the last batch

Rung 1:

—] [Clear_Buf———[FLL 0  Buffer  6]———

Scan 1 — Clear_Buf = 0. Buffer reads 1, 2, 3, 4, 5, 6. The literal Source has no value line.

Scan 2 — Clear_Buf = 1. Every element reads 0.

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See Also

• COP — Copy File (array to array)
• CLR — Clear (one tag to zero)
• MOV — Move (one element)
• Move/Logical Instructions — Category index

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Notes

Partial fills. FLL 0 Buffer[3] 3 clears the last three elements only.

STRING arrays. FLL "" Names 8 blanks eight strings; a quoted literal or a STRING tag is the Source.

The block never colours. Watch the rung wire and the Dest value list.