LOADTL Section in the postprocessor

Are you wondering what POSTF is?

The POSTF function is used in the FIL code for pretty much anything that is important. It's a strange function that is called with the number of arguments that are needed for a specific data inquiry. The general format of a call is POSTF ( number, arg1, arg2,...)

The first integer supplied to the POSTF function tells it what actual operation you want it to perform. POSTF(13) for example is telling the post processor to process the current line of NCL code.

I find the POSTF stuff to be pretty frustrating, because when you look at the FIL code, unless you have memorized what the first integer means, you have no idea what that particular invocation of the function will do. I have to look up the function in the documentation I have, or search for it online, etc.

Also, notice that every call to POSTF assigns the return code to a variable, often a "throwaway" variable. The return code can be useful if something has gone wrong, or if the POSTF operation being performed is supposed to return a numeric or other type of result.

What is done with the line of code POSTF is looking at depends on what it contains. The CIMFIL block you show apparently looks at the tool change line and if necessary, adds more arguments to it before sending it for processing. It's like you're erasing the current "line" on the "tape", then writing in a new expanded "line", then letting the program interpret that new "line".

As for what prep codes are output when a tool change happens, those could be "hard coded" into your FIL code, like the G90 added with an INSERT/ statement. They could also be specified in the post-processor settings you can set from within Creo, via:

Applications->NC Post Processor->Machine Codes->Tool Change Sequence

You could handle all the outputting of information in your FIL code and never let the post processor interpret things, if you want, by not having the POSTF(13) line in the CIMFIL block.

If you are going to be modifying FIL code, I'd highly recommend finding a copy of some sort of document detailing the POSTF functions. There's no way to guess as to what a function is doing, unless you have example code that is well commented or easy to interpret.