User`s guide

Chapter 5 Digitizing 133
can select the level triggering shown in Figure 27 merely by specifying the
LEVEL trigger event (TRIG LEVEL command).
The following program specifies level triggering to occur when the input
signal reaches +5V (50% of the 10V range) on a negative slope
(AC-coupled). Assuming the input signal has a peak value of 10V and the
measurement range is 10V, the result is shown in Figure 27.
10OUTPUT 722;"PRESET DIG" !DCV DIGITIZING, 10V RANGE
20OUTPUT 722;"TRIG LEVEL" !SELECT LEVEL TRIGGER EVENT
30OUTPUT 722;"SLOPE NEG" !TRIGGER ON NEGATIVE SLOPE OF SIGNAL
40OUTPUT 722;"LEVEL 50, AC" !LEVEL TRIGGER AT 50% OF 10V RANGE,
45 !AC-COUPLED
50END
The following program specifies level triggering to occur when the input
signal reaches -5V (-50% of the 10V range) on a positive slope (AC-coupled).
Assuming the input signal has a peak value of ±10V and the measurement
range is 10V, the result is shown in Figure 28.
10OUTPUT 722;"PRESET DIG" !DCV DIGITIZING, 10V RANGE
20OUTPUT 722;"TRIG LEVEL" !SELECT LEVEL TRIGGER EVENT
30OUTPUT 722;"SLOPE POS" !TRIGGER ON POSITIVE SLOPE OF SIGNAL
40OUTPUT 722;"LEVEL -50,AC" !LEVEL TRIGGER AT -50% OF 10V RANGE,
45 !(-5V) AC-COUPLED
50END
In the following program the input signal is DC-coupled to the level detection
circuitry and consists of a 5V peak AC signal riding on a -5V DC level. In
Figure 27. Level triggering, 50%, neg. slope, AC-coupled
Figure 28. Level triggering, -50%, pos. slope, AC-coupled