Rewrite old pal programs for PAL2020

Last change: Jul 28, 2023

With the PAL2020 reform, some commands in the PAL coding were changed, so that programs written according to PAL2008 or PAL 2012 partly do not run anymore and lead to error messages in the newer PAL2020 simulators (or PAL2020 C/Y or PAL2020 3+2 respectively).

For the changes of the grooving or recessing cycles in turning, which are still called G86 or G88 but have many new or changed cycle addresses, the NC blocks must be practically rewritten. Here it is recommended to first comment out the "old" cycle blocks in the "free editor" and then to reprogram them in the guided mode ("F7 editor"). Note, however, that commenting out changes the line numbering (which affects jumps with G23), since pure comment lines have no line numbers. To avoid this, you can use a trick and write the previous cycle as a comment after a regular (innocuous) NC block. Example:

N28 M1 ; G86 X60 Z-55 ET54 EB6 RO-0.5

It is easy to "translate" PAL2008 or PAL2012 commands (for layer selection) with all other functions, because here there is a simple assignment between old and new:

In the "Free Editor" you can use the "Find/Replace" function or also the shortcut Ctrl+H for this. If you have previously programmed the LAGER3 exercise from the "Plane Swivel" workbook according to PAL2012, take this as an example. After loading in "PAL2022" mode, a message "The NC program is faulty!" will appear, which you acknowledge with "F10". Marked is the last block in the program that does not correspond to the coding according to PAL2020. "N65 G17 CR180 AR90". Here (and in many other lines in the program) G17 must be replaced by G15.

So select "F1 Search/Replace" and enter "G17" in the "Search for" field and "G15" in the "Replace with" field. Select "F3 Replace all" and accept the dialog with "F10" and in the whole document G17 will be replaced by G15.

Subsequently, when you try to change to the "guided mode" again, the line "N45 G48 G40 R10 Z0" is marked as incorrect, because after PAL2020 the commands for tangential approach and departure have changed, too. Replace therefore (following same principle as above) "G48 G40 R by "G40 G46 RR" in the entire document and afterwards also "G41 G45 D" by "G41 G45 DL". For the program LAGER3 all necessary replacements are made and you can change with "F7 editor" again into the "guided mode" and simulate there the program with "F9 Simulation".

A complete table comparing "PAL2008/PAL2012" and "PAL2020" (as of summer 2023) can be found below:

Other changes do not necessarily require the revision of existing programs, but may have an impact in the simulation: