PMAC Quick Reference Guide 9. In a motion program, 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. 10.
The CLOSE statement closes the currently opened buffer. This should be used immediately after the entry of a motion, PLC, rotary, etc. buffer. If the buffer is left open, subsequent statements that are intended as on-line commands (e.g. P1=0 ) will get entered into the buffer instead. It is good practice to have close at the beginning and end of any file to be downloaded to PMAC. When PMAC receives a CLOSE command, it appends a RETURN statement to the end of the open program buffer automatically. If any program or PLC in PMAC is structured improperly (e.g.
no ENDIF or ENDWHILE to match an IF or WHILE ), PMAC will report an ERR003 at the CLOSE command for any buffer until the problem is fixed. Example: close ; Close any buffer opened delete gather ; Erase unwanted gathered data undefine all ; Erase coordinate definitions in all coordinate systems #1->2000X ; Motor #1 is defined as axes X OPEN PROG 1 CLEAR ; Open buffer to be written LINEAR ; Linear interpolation INC ; Incremental mode TA100 ; Acceleration time is 100 msec TS0 ; No S-curve acceleration component F50 ; Feedrate is 50 Units per Ix90 msec X1 ; One unit of distance, 2000 encoder counts CLOSE ; Close written buffer, program one Running a Motion Program 1.
Select the coordinate system where the motion program will be running. This is done by issuing the & command followed by the coordinate system number, e.g., &1 for the coordinate system one. 2. Select the program that to run with the B{constant} command, where the {constant} represents the number of the motion program buffer. Use the B command to change motion programs, and after any motion program buffer has been opened.
It is not necessary to use it if running the same motion program repeatedly without modification; when PMAC finishes executing a motion program, the program counter for the coordinate system is set automatically to point to the beginning of that program, ready to run it again. 3. Once it is pointing to the motion program to run, issue the command to start execution of the program. For continuous execution of the program, use the R command ( for all coordinate systems simultaneously). The program will execute all the way through unless stopped by command or an error condition. 4.
To execute just one move or a small section of the program, use the S command ( for all coordinate systems simultaneously). The program will execute to the first move DWELL , DELAY , or if it first encounters a BLOCKSTART command, it will execute to the BLOCKSTOP command. 46 Motion Programs