FAL Instruction - Understanding What Previous Programmer was doing

[BobLfoot 303]

I am trying to figure out why the previous programmer used a FAL Instruction and not a CPT instruction.

The destination is a single REAL not an array.  The FAL.POS tag is not used anywhere else in the program.

I can't find a reason for using FAL.  Any Thought?

[Michael Lloyd 86]

Copied this from the help file

Description

The FAL instruction performs the same operations on arrays as the CPT instruction performs on elements.

Added rambling thoughts-

Length 520 double integers. It's set to INC so it's going to step through every time the HSC see new data. 

So where's the math (computation) that's being performed? 

This is why I prefer a clear and concise description to blah_blah_blahty_blah tag structure :/

[BobLfoot 303]

@Michael Lloyd if you examine the FAL Instruction you'll see an Expression Field.  This is where the math is done.Top_Stored_Value * Encoder_Top .

My question is the destination makes no reference to an array, but is a single REAL.

If he had used TOP_NEW_VALUE [FAL_Top.POS] for the destination , I could see using it.

[chelton 69]

Certainly saves memory  Don't need to use an ONS doing it that way

[Michael Lloyd 86]

3 hours ago, BobLfoot said:

@Michael Lloyd if you examine the FAL Instruction you'll see an Expression Field.  This is where the math is done.Top_Stored_Value * Encoder_Top .

My question is the destination makes no reference to an array, but is a single REAL.

If he had used TOP_NEW_VALUE [FAL_Top.POS] for the destination , I could see using it.

I hate when something is right in front of me and I don't see it :)

It looks like it performs the function on the array variables (FAL_Top or does that point to an array?), one at a time every time Top_New_Data cycles, and updates the single Real value?

[chelton 69]

@BobLfoot does a cross ref of FAL_Top

Bring up any .dn or other flags used? 

They might be using it as a counter and compute in one instruction 

[BobLfoot 303]

Nothing found by Cross Referencing the FAL, but as I study the data it looks like they did not imagine they'd get out of range data and had to introduce a filtering mechanism and then save the datums to an FFL.  The FAL was probably the first pass storage attempt and they just changed from an array to a single real.