Hello friends  

if I just want to read high speed input using s71214c plc then can I use notation ":P" with high speed input in OB1 or

I have to use HSC for these input ??

Thanks in advance

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Split from Hardware Interrupt.

hey thanks 

actually my problem is that my input is very fast it will come for an microsecond width

so I want to detect it in my PLC s71214.

because scan time for my PLC is upto 10-15ms

So can u help me how to do this??

AutoGen_3102106

hey thanks 

actually my problem is that my input is very fast it will come for an microsecond width

so I want to detect it in my PLC s71214.

because scan time for my PLC is upto 10-15ms

So can u help me how to do this??

Is this signal a repeated signal or just very short once-off pulse? 

Only the short burst pulse is detailed now.

The inputs on the CPU can be configured to do "pulse catching". This means that a very short pulse will be extended for at least one scan cycle. This is ideal for a short signal to which you only need to react upon in the normal scan of the PLC. There is not :P modifier required.

The next option is to create a hardware interrupt. This will generate an event that will jump to an OB code that will execute at the moment the signal takes place. This interrupting mechanism will not work well if the pulse is repeated to often.

Thanks,

Its actually single pulse only

I will try by Pulse catch 

Thanks again