trick or tip
- Thread starter twbrock
- Start date
Mickey
Lifetime Supporting Member
Use the "Free Running Clcok" S:4 status bits. See PDF below for more info.
ndzied1
Lifetime Supporting Member
One other method that I have seen is to use a single timer that resets itself. Then do a Less than comparison with the .ACC value to drive the flashed.
For instance, .01 time base, preset of 200 (2 sec) and timer resets itself. Then drive the flasher with LES T4:x.ACC 100. Then the flasher is on for the first second and off for the next second.
This method has the advantage of non symmetrical on/off times or even synchronized flashing by using multiple limit instructions to look for certain parts of the same timer cycle.
For instance, .01 time base, preset of 200 (2 sec) and timer resets itself. Then drive the flasher with LES T4:x.ACC 100. Then the flasher is on for the first second and off for the next second.
This method has the advantage of non symmetrical on/off times or even synchronized flashing by using multiple limit instructions to look for certain parts of the same timer cycle.
geniusintraining
Lifetime Supporting Member + Moderator
Not sure if it will help but see this.... may give you some ideas on what not to do 
First rung is just a timer that resets itself
Second rung takes the time and counts up
Third moves the counter to a output word
Forth resets the counter
This is just making the lights flash in sequence as the counter counts up.... a little better then just turning them on and I am sure that there are 100 ways of doing this better....
Hope it give you ideas
First rung is just a timer that resets itself
Second rung takes the time and counts up
Third moves the counter to a output word
Forth resets the counter
This is just making the lights flash in sequence as the counter counts up.... a little better then just turning them on
and I am sure that there are 100 ways of doing this better....Hope it give you ideas
shoelesscraig
Member
All of the suggestions are great, but really most of them are overkill. If you just need to make an output flash, use Mickey's suggestion. The free running clock S:4 bits are the easiest way. Why write a bunch of logic with timers and counters when you can add 1 instruction to your rung (unless you want some sort of a fancy flashing sequence)?
dmroeder
Lifetime Supporting Member
Amen, free running clock is the way to go.
Mickey
Lifetime Supporting Member
Your welcome, let us know how it works out.
Mickey
Lifetime Supporting Member
Good to hear, and thanks for letting us know. Always good to hear success stories.
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