Logo!8 data loging. 5 last values on HMI TDE

[marcinmrag 0]

Hello,

I would like to ask if is possible to store for example 5 last value from counter and display this on logo HMI? I would like to create something like a history for last 5 counts. But im afraid that is impossible to do.

[markyspicer 3]

17 hours ago, marcinmrag said:

store for example 5 last value from counter

you have to identify what type of triggering are you referring to.  is it schedule(time-based), value change, etc.

from there you can manipulate which data you want to store.

[marcinmrag 0]

I use a counter. I count value of full movements of cylinder until it's stop. I would like to do history of last 5 counts. And display this values for example when F2 i pressed

[Tinkerman42 0]

One way to do this is to create 5 arithmetic computation blocks.  Connect the count you want to track to the first item of a computation block (let's call it B101) and leave the other 3 items set to zero. Now connect the output of the block (B101) to an analog flag (lets call it AM1).  Now take AM1 and connect it to the first item of a second computation block (let's call it B102).  Now connect the output of the block (B102) to another analog flag (lets call it AM2).  And so on and so on.  You get the idea, so the last part would be AM4 connected to the first item on B105 and the output of B105 connected to AM5.

Now you need a trigger that goes high when your count is ready to be read.  Make sure the trigger is one shotted and attach this to the enable connection on all of the Computation blocks (B101-B105).  Be sure each Computation block is set so that the output maintains last value when disabled.  This way the new count will be read and saved in the first block and the historical readings will move down in the other blocks and then hold until the next count is ready.

Your count history will be in both AM1-AM5 and the output of B101-B105.

If you find that you are capturing the count too early you can add an M flag between the one shot trigger and the Enables on the Blocks. If you are capturing the count too late add an Analog Flag (AM) between the count and the First Computation Block (B101 in my example).

Using this method you do not have any restrictions on what block numbers are used.  

You may have to tweak it a bit but this should get you what you want.