BNC 645 - Manual (Page 74)

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current cycle and then stops at the same voltage level as the
starting burst phase. For noise waveform, the output stops
immediately when the external signal turns false.
Trigger Out Signal
Model 645 may be configured to send out a TTL-compatible square wave
at the Ext Trig connector on the rear panel with either a rising or a falling
edge at the beginning of a sweep or burst.
z
With internal trigger source, the trigger out signal is a square
wave with 50% duty cycle. The period of the trigger out signal is
equal to the sweep time or the burst period.
z
With the manual trigger or BUS trigger source, the trigger out
signal is a pulse with pulse width > 1 μs.
z
With external trigger source, there is no trigger out signal as the
Ext Trig connector is used to receive the trigger input signal.
How to set up the trigger out signal
1. After sweep or burst mode is activated, press the Trig Setup
softkey to enter the trigger setup submenu.
2. Press the Trig Out softkey and then select among OFF, rising-edge
trigger and falling-edge trigger.
3. Press the softkey under DONE to finish the setting.
Remote interface operation
OutPut:TRIGger {OFF|ON}
OutPut:TRIGger:SLOPe {POSitive|NEGative}
5.2 Storing the instrument state
Model 645 provides five storage locations in non-volatile memory for
user to store instrument state. The stored instrument state holds all the
parameters for the selected function, including the waveform, frequency,
dc offset, amplitude, duty cycle, symmetry, modulation type and
modulation parameters.
The first location, indexed at “0”, is automatically assigned for
instrument state at power-down, but you can use any of these locations