Hey, all. I've inherited an R30iB Mate that has some BG Logic I'm trying to figure out, that makes use of $FAST_CLOCK:
IF (F[7]=ON AND DO[112]=OFF) THEN ;
GO[1]=6 ;
IF (DO[111]=OFF),R[9]=($FAST_CLOCK) ;
IF ($FAST_CLOCK<=R[9]),DO[111]=(ON) ;
IF (DI[102]=OFF),DO[111]=(OFF) ;
ENDIF ;
F7, DO102, and DO112 are controlled from the "foreground" program.
Now, if I'm reading this correctly, DO111 will only turn On once $FAST_CLOCK rolls over the top, which seems like it would be a huge time delay. However, I can't find any references on $FAST_CLOCK's max and min values, and how/when it rolls over -- the System Variables manual shows all these as "Not Available" .
But watching this program run, DO111 is coming on almost immediately after F7 is set On and DO112 is set Off. So there must be something about $FAST_CLOCK that I'm not understanding correctly.
I have done a full program dump and confirmed that DO111 is not turned On from any other logic in the controller.