SystemTask
SystemTask Give DAs a chance to perform periodic actions Call SystemTask at least once each time through your event loop. It lets the Desk Manager process such periodic DA events as updating the display of a
clock.
Notes: SystemTask should be called at least once every 17ms (1/60-th of a second). Normal usage is to put it inside a part of the event loop that
always gets executed:
main()
. ... initialize other stuff ...
.
while (TRUE) fi/* Loop forever; terminate via */ }
EventLoop()
{
MaintainCursor();
MaintainMenus();
.
. ... process events ...
.
}
}
DAs wanting a timeslice every so often should set bit 5 of the drvrFlags
word and a tick count in drvrDelay in the driver header. You should not
depend on any particular accuracy, since an application may fail to call
SystemTask often enough (e.g., when saving a file). To receive periodic timeslices with more accuracy, install a vertical retrace task via VInstall or a timer interrupt task via InsTime.