Hi, Roger,

Another little "drama" in my uneventful life! Could you explain how DT800 reads and calculates TRF (pulse width)? Is it done within a single Schedule read? What schedule trigger should I use with this function?

I am using TRF in my measurements using as a trigger "Trigger on Events" - trigger on raising and falling transition. While this works, I get two lines of data for each read. I read a string of pulses, btw. I have tried triggering on other events, without much success.

Basically, I do not understand the DT operation in this mode. Can you help and explain, please? Cheers, Chris Ah, yes! Forgot to add, that for Signal, I am using - DIGITAL. Maybe, I should use TIME. But in either case, I do not understand how DT can read such value - two inputs (up and down)- in one read.

fredflinston

Good afternoon Fred,

Sorry about the late reply, I'm trolling through to see if I've missed any and found this. The dataTaker needs to scan the schedule twice and then it compares the current state of the digital input with the previous state.

So the best way to check the TRF, TFR, TFF or TRR is to trigger the schedule on any change of state of the digital input and then determine the time difference. For example this code will work

BEGIN
RA1E
1DS(TRF)
END

This code will report zero time one pass and the Time of Rising edge to Falling edge (TRF)the next. This code won't work

BEGIN
RA1+E
1DS(TRR)
END

This won't report the time between rising edges because the schedule is triggered on rising edges so when the edge rise the logger does not see a state change.

Cheers,
Roger