AB Pico Flashing Lights Varying Sequences

1769-L12DWD-ND ser. B

Ok guys, I'm stuck and could use some help.
I have 5 positions of a motor I am monitoring and have set up an output to flash an indicator light to flash a pattern based on the 5 positions where the motor is stopped.
Example:
Position one = On 0.50sec, off 4.50sec (one timer set as flashing 0.50 on, 4.50 off)
Position two = On 0.50sec, off 0.50sec, On 0.50sec, off 3.50sec (two timers started on the same rung, first timer set as flashing 0.50 on, 0.50 off, second timer set as flashing 1.50 sec on, 3.50 off)
Next positions three to four similar to position two, but longer second timer on for 3 to 4 pulses)
and lastly Position 5 uses one timer with on 0.50sec, off 0.50sec
Problem I'm having is the timers using the two timers slowly go out of phase, like they aren't running equall 5 second cycles, is this typical with Pico? Is there a different way to get the varying patterns of flashing I'm looking for with a Pico?

Problem I'm having is the timers using the two timers slowly go out of phase, like they aren't running equall 5 second cycles, is this typical with Pico?

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If you use two timers at different places in the scanned program, they probably will not keep the exact same time.

Is there a different way to get the varying patterns of flashing I'm looking for with a Pico?

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Yes, I am sure there is a way. If you avoid using two different timer bits (or avoid using more than one timer) on the same rung to create a flasher, that will go a long way toward solving the problem. For example, on Rung 78, you use a bit call T05 "Error Flasher" to control another timer called TT06 "Position Pulse Flasher". IF T05 is indeed a flasher bit (going on and off), then TT06 timer will also go on and off at that same rate, no matter if you have TT06 output set to flash at some other rate. I don't think you will be able to coordinate these timers that way to allow one flashing bit to control another flashing timer.

You have 16 counters. A counter can be triggered by a 0.5 second timer, and can count any number of on/off cycles. Have you thought of using counters controlled by ONE timer to create all of your position codes? With one 0.5 second timer, could you not create all of your position codes using numerous counters counting up to different amounts of 0.5 second cycles? For example, a 4.5 second time would be when Counter Cx reaches 4.5 seconds/0.5 seconds, or "9".

Better still, why such an elaborate code, when you have only 5 positions? Try to make it as easy to read as possible. Pretend you have never seen it before, then what would you think these codes mean?
On, Off 1 time, pause 1.5 seconds, repeat.
On, Off 2 times, pause 1.5 seconds, repeat.
On, Off 3 times, pause 1.5 seconds, repeat.
On, Off 4 times, pause 1.5 seconds, repeat.
On, Off 5 times, pause 1.5 seconds, repeat.

Here is how I have done it in RSLogix, using one flasher bit, one timer for pause between codes, and two counters. This allows flashing up to 99 2-digit codes, although the lower numbers from 1 to 55 are the most practical.

For the Pico, because you cannot write to the Counter preset values, you will need a counter for each of the 5 positions.

Lancie1,
You helped clear this all up, I just got back to it today and within a few minutes of programming after rereading your posts I have stable and more user friendly flashes for all positions. Thank you.

On, Off 1 time, pause 1.5 seconds, repeat.
On, Off 2 times, pause 1.5 seconds, repeat.
On, Off 3 times, pause 1.5 seconds, repeat.
On, Off 4 times, pause 1.5 seconds, repeat.
On, Off 5 times, pause 1.5 seconds, repeat.

Great. I am glad that you got it working.