S7 300 capturing a short duration input

[ratcliffe_ic 2]

I need to catch an input changing state which has a very short duration and I'm currently missing it due to scan time.  Is there a way in Siemens to improve the chances of catching a change by programming e.g. using something similar to a Selectable timed interrupt (STI) from the Allen-Bradley world or maybe a FAST TASK?

Thanks in advance for any suggestions

 

[Moggie 17]

Try the following

L  PIWxx

T  IWxx

[Joe E. 259]

Check out hardware interrupts, in case your input module is capable:

https://support.industry.siemens.com/cs/document/23657941/what-is-a-hardware-interrupt-and-how-do-they-work-in-the-s7-300-system-?dti=0&lc=en-WW

 

This goes into a little detail about what Moggie is talking about:

https://support.industry.siemens.com/cs/document/18325417/where-and-when-do-you-need-peripheral-addressing-?dti=0&lc=en-WW