RSLogix 5000 STL Timers

I haven't used used timers and STL together, so thought I'd try them on my next project!


I have the following code example:

//#Region Alarm_Ack

SBR_Alarms_TIMERS[25].EN :=
HMI_CMDS_SS_Dint.18 or
(SBR_Alarms_TIMERS[25].EN and
not SBR_Alarms_TIMERS[25].DN);

//#End_Region

Click to expand...

So basically I was hoping when someone presses the HMI cmd `HMI_CMDS_SS_Dint.18` (which is only active for 1 scan),

then
`SBR_Alarms_TIMERS[25].EN` would become `1` (which it does) and hence latch `SBR_Alarms_TIMERS[25].EN`
Until:
SBR_Alarms_TIMERS[25].DN becomes active 3 seconds later (3000 set to `.PRE` elsewhere).


Problem is:
.EN becomes a 1 as expected
.DN never does...?


Any help?


Thanks
Rob

Try .TT instead of .EN and NOT .DN

Do you call The timer anywhere ?

Rob.Hill said:

Problem is:
.EN becomes a 1 as expected
.DN never does...?

Click to expand...

Are you sure? Or could .DN become 1 for 1 scan but you never see it. Try adding this





or feed the .DN into a counter, and see if either that float, or the counter, is incremented.


I think that replacing (.EN AND NOT .DN) with .TT will not change anything, because that is what .TT is.

Jobbe9000 said:

Do you call The timer anywhere ?

Click to expand...

This.

Thanks for the responses.


I will get chance to get back online this afternoon for some testing.


I think the issue is: 'Do you call the timer anywhere'


- unfortunately no! I mistakenly believed only TONR timers needed to be called and that calling the '.EN' bit would suffice. Obviously this isnt the case.


Is it possible to work with only TON timers in ST or does it have to be TONR?


I'll get chance to google later after travelling, but if anyone feels like making it easy for me - how to call TON (if poss)/ TONR


Thanks for the support


Rob