Tektronix TDS 640A Sprinkler User Manual


 
Appendix B: Algorithms
Appendices
AĆ10
MidRef + (Hysteresis x Amplitude)
MidRef - (Hysteresis x Amplitude)
MidRef
MCross1
(StartCycle)
MCross2
MCross3
(EndCycle)
Figure AĆ1:ăMCross Calculations
Waveform[<0.0 ... RecordLength-1.0>] Ċ holds the acquired data.
TPOS Ċ is the location of the sample just before the trigger point (the time
reference zero sample). In other terms, it contains the domain reference
location. This location is where time = 0.
TSOFF Ċ is the offset between TPOS and the actual trigger point. In other
words, it is the trigger sample offset. Values range between 0.0 and 1.0
samples. This value is determined by the instrument when it receives a
trigger. The actual zero reference (trigger) location in the measurement
record is at (TPOS+TSOFF).
The automated measurements are defined and calculated as follows.
Amplitude
Amplitude = High - Low
Area
The arithmetic area for one waveform. Remember that one waveform is not
necessarily equal to one cycle. For cyclical data you may prefer to use the
cycle area rather than the arithmetic area.
if Start = End then return the (interpolated) value at Start.
Otherwise,
Area=
ŕ
End
Start
Waveform(t)dt
Measurement
Algorithms