Manual

Introduction to Programming

Chapter 10

M99 code acts as a return command in both sub- and main programs;

however, there are specific differences:

Using M99 in a Main Program

If you use M99

in a:

M99:

Main program executes all commandsin theblock, regardless if information

is programmedin theblock tothe right of theM99 command

clears allmodal codessimilar to anM02 or M30 (simulates

start-up conditions)

resets thecurrent main programto thefirst block

automatically performsa cyclestart on theprogram after it is

reset and program execution startsover.

Subprogram tells the controlthe end of a subprogram

will not mergeany commandswithin afile that isused asa

subprogram andfollows a M99 codein themain program into

the calling program.

Using M99 in a Subprogram

Program the M99 code anywhere in a program block, provided no axis

words are programmed to the left of M99. Any information (other than

axis words) programmed to the left of M99 is executed as part of the

subprogram, while information (including axis words) programmed in the

block to the right of the M99 command is ignored.

If you program: Then:

M99X10; X10 is ignored inthis subprogramblock

X10M99; X10 generates an errorin thissubprogram

M03M99; M03 isexecuted asnormal inthis subprogram

10.3.2

Main and Subprogram

Return (M99)