User's Manual

PMAC User Manual

20 Getting Started with PMAC

When finished entering the program, type CLOSE <CR> to exit the program buffer. To enter a new

program in the place of the one in the buffer, open the buffer, type CLEAR, and enter the new program. An

example follows:

OPEN PROG 1

CLEAR ; erase old program

F2.36 ; 2.36 in/sec

X5.346 Y0 ; first side of square

X5.346 Y5.346 ; second side

X0 Y5.346 ; third side

X0 Y0

; fourth side

Using the Program Editor

It is easiest to type programs using the program editor in the PC Executive (terminal) Program. Here the

program can be changed at will, and then it can be downloaded to the card by selecting the Download

Editor to PMAC menu option, or by hitting <ALT-D> when the editor screen is displayed. Include in each

program space the lines to open the buffer, to clear out the old program, and to close the buffer at the end.

Executing a Motion Program

Starting the Program

With a program held in PMAC buffer, it is easy to run. To run program 1, make sure the coordinate system

to run the program is addressed (&1 in this case), type B1<CR> (point to beginning of program 1), then

type R<CR>. The B command with a number makes the specified program the working (operative)

program for the coordinate system. The R command will start execution of the program.

Stopping the Program

There are several ways to stop a running program. Q<CR> (Quit) stops the program at the end of the

presently executing move. A<CR> (Abort) causes the motors in the coordinate system to start decelerating

immediately. Both of these commands leave the program ready to execute (run or step) the next line in the

program. To re-start the program at the beginning, type B<CR> (the B command without a number operates

on the current working program). This resets the program counter to the top (completion of a program

automatically resets the counter to the top).

Remember that the motor velocity and acceleration limits (Ix16 and Ix17) are in effect for all motors in the

coordinate system. If a motor is asked to exceed one of these limits, all motors in the coordinate system are

slowed to honor the limit. If the programmed moves seem slower than what as expected, this could be the

cause.

Refining the Program

Few times will the program work exactly right the first time. Go through an iterative process of editing,

downloading, executing, and evaluating. This is one of the key reasons for using the program editor. The

required changes can be made in the editor without re-typing the entire program. Then, the entire revised

program can be downloaded to PMAC. This process is why it is a good idea to have the CLEAR command

immediately after the OPEN command: it erases the old version in PMAC so the new version can replace it.

There is no reason in this process to upload the program from PMAC. The program editor maintains its

copy even after the download, and it keeps comments with it. The only reasons to upload a program are to

confirm that it is downloaded properly, and to restore a program that was lost by the host computer.