On a completely unrelated subject, why can't I change/modify the input bit while monitoring?

I can however switch over to the Force Watch Table but I don't like doing that. 

[seperate question moved to:FWUPDATE.S7S - cannot update PLC through Web server, it fails with return message 400 bad Request]

Thanks alot!

- G

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Split from Siemens S7 1214C DC/DC/DC .

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Split from why can't I change/modify the input bit while monitoring?.

stoilovgoran

<snip>
why can't I change/modify the input bit while monitoring?

I can however switch over to the Force Watch Table but I don't like doing that.
</snip>

Hello.

The memory space that you know as "inputs" are repeatedly updated from the physical inputs. The default setting has the inputs updated at every cycle of OB1.

The update of the inputs can be changed in the hardware configuration as hinted by the following picture. Making the option "NONE" means the input will only be updated if an input is read with a modifier key like: "myInput":P    (colon papa).

0_Einstein

The topic is not completely accurate since you are changing the input bit, for a very short time.  As qwazee pointed out, as soon as the PLC updates the input process image (which happens every scan on s7-1200's), your short-term modification is gone.

Got it, I was just trying something out as I had nothing at home to attach as an input to the device, but I am glad we got that out of the way.

Thanks!

Hello,

Work with mapped variables, create a DB with all inputs and make a SCL block that takes the values from there: "Mapped_Input" := "Real_Input". You can automate the process with an Excel file. Create a "Sim_Mode" bit that activates the mapping block, and use the mapped variables in your project.

I know this is not a quick fix, more a project making methodology, but it saves a lot of time when simulating / testing, you slit the screen and only double-press for switching / modifying values. Extend it to the HMI with an engineer level faceplate and you'll pass through any start-up.