Agilent Technologies E1441A user service Triggering the Function Generator, Trigger Slope

Triggering the Function Generator

Note

Applies only to counted bursts and frequency sweep, not gated modes such as Gated Bursts, or FSK modulation. You can issue triggers for bursts and sweeps using internal triggering or external triggering. Topics covered on triggering are:

•“Trigger Source Choices” on page 52

•“Ext Trig / FSK / Burst Input Terminal” on page 54

Trigger Slope

The Agilent E1441A includes a choice of trigger polarity when the source in an external or one of the 8 VXIbus TTLTRG lines. The command to select the trigger polarity is:

TRIGger:SLOPe POSitive NEGative

TRIG:SLOPE selects the slope of the trigger source only. Where the external trigger sources ("Ext Trig" and TTLTRG lines) are being used as a gating signal for Burst and FSK, the setting of TRIG:SLOPE is ignored

POS: (*RST state) For TRIG:SOUR EXT (Ext Trig/FSK/Burst terminal); triggers on positive going TTL signal.

For TRIG:SOUR TTLT<0-7>; triggers on negative going signal on VXIbus TTLTRG line (ground true logic)

NEG:For TRIG:SOUR EXT (Ext Trig/FSK/Burst terminal); triggers on negative going TTL signal.

For TRIG:SOUR TTLT<0-7>; triggers on positive going signal on VXIbus TTLTRG line (+ true logic)

Trigger Source Choices

Again, the applies only to counted burst and sweep. You must specify the source from which the function generator will accept a trigger.

The function generator will accept a software (bus) trigger, a hardware trigger from the Ext Trig terminal or VXIbus TTLTRG lines, or an immediate internal trigger.

The trigger source setting is stored in volatile memory; the source is set to immediate when power has been off or after resetting the module.

To select the trigger source, use the following command.

TRIGger:SOURce BUSEXTernalIMMediateTTLTrg<0-7>

The APPLy command automatically sets the trigger source to IMMediate

52 Agilent E1441A Application Information Chapter 2