Delta Tau GEO BRICK LV User Manual

 

 

Motion programs are Turbo PMAC’s chief mechanism for describing the desired motion with the 
associated math, logic, and I/O operations.  They provide a simple, yet powerful and flexible means for 
describing the motion and operations synchronous to that motion. 

Turbo PMAC can hold up to 224 motion programs at one time.  Any coordinate system can run any of 
these programs at any time, even if another coordinate system is already executing the same program.  
Turbo PMAC can run as many motion programs simultaneously as there are coordinate systems defined 
on the card (up to 16).  A motion program can call any other motion program as a subprogram, with or 
without arguments.   

Turbo PMAC’s motion program language is perhaps best described as a cross between a high-level 
computer language like BASIC or Pascal, and G-Code (RS-274) machine tool language.  In fact, it can 
accept straight “G-Code” programs directly, provided it has been set up properly.  It has the 
computational and logical constructs of a computer language, and move specification constructs very 
much like machine tool languages.  Numerical values in the program can be specified as constants or 
expressions. 

A powerful feature of Turbo PMAC motion programs is their automatic sequencing of calculations in 
synchronization with the programmed moves.  Unlike many motion-programming languages, it is not 
necessary to include in your program explicit structures to wait for the end of a programmed move.  
Instead, the Turbo PMAC’s operating system automatically monitors the progress of the programmed 
move execution and triggers pending calculations (motion, I/O, and/or logic) at the end of a programmed 
move.  This greatly simplifies the writing of motion-program sequences. 

A key implication of this scheme is that calculations in motion programs occur only at the boundaries of 
programmed moves.  If you have calculations that you want to occur at other times, these calculations 
should be executed in Turbo PMAC PLC programs instead.  See the Writing and Executing PLC 
Programs section of this manual for details. 

In a motion program, Turbo PMAC has WHILE loops and IF...ELSE branches that control program 
flow.  These constructs can be nested indefinitely.  In addition, there are GOTO statements, with either 
constant or variable arguments (the variable GOTO can perform the same function as a Case statement).  
GOSUB statements (constant or variable destination) allow subroutines to be executed within a program.  
CALL statements permit other programs to be entered as subprograms.  Entry to the subprogram does not 
have to be at the beginning – the statement CALL 20.15000 causes entry into Program 20 at line 
N15000.  GOSUBs and CALLs can be nested only 15 deep. 

To handle machine-tool-style G-codes, which provide direct access to part programs created by 
CAD/CAM programs, Turbo PMAC treats a Gnn statement as CALL 1000.nn000.  The following 
values on the line (e.g. X1000) can be treated as parameters to be passed, as for a canned cycle, or the 
subprogram can execute without arguments, return, and execute the rest of the line (as for a modal G-
code).  The machine tool designer writes Program 1000 to implement the G-codes as he wishes, allowing 
customization and enhancements.  Delta Tau provides a sample file implementing all of the standard G-
codes.  M, S, T, and D codes are similarly implemented.