External Trigger I/OEach of the seven pins can be configured as trigger inputs or trigger outputs. The polarity of the pinscan also be configured. When you program trigger polarity, POSitive means a rising edge andNEGative means a falling edge. Pin 8 is the signal common for the trigger pins. For an overview of thetrigger system, refer to Trigger Overview.When configured as a trigger input, you can apply either a negative-going or a positive-going pulse tothe designated trigger input pin. The trigger latency is 5 microseconds. The minimum pulse width is 4microseconds for positive-going signals, and 10 microseconds for negative-going signals. The pin’spolarity setting determines which edge generates a trigger-in event.When configured as a trigger output, the designated trigger pin will generate a 10 microsecond-widepulse when a Trigger Out occurs. Depending on the polarity setting, it can be either positive-going(rising edge) or negative-going (falling-edge) when referenced to common.Front Panel Menu Reference SCPI CommandSelect System\IO\DigPort\Pins.Select a pin in the Pin field.In the Function field, select either the Trig In or Trig Out function.In the Polarity field, select either Positive or Negative.To select the trigger output function for pin 1:DIG:PIN1:FUNC TOUTTo select the trigger input function for pin 2:DIG:PIN2:FUNC TINPTo select the pin polarity:DIG:PIN1:POL POSDIG:PIN2:POL POSFault OutputPins 1 and 2 can be configured as a fault-output pair. The Fault Output function enables a faultcondition to generate a protection fault signal on the digital port. Refer to Programming OutputProtection for a list of protection signals.Both pins 1 and 2 are dedicated to this function. Pin 1 is the Fault output; pin 2 is the common for pin 1.This provides for an optically-isolated output. The polarity of pin 1 can also be configured. When thepin polarity is POSitive, a fault condition causes the isolated output to conduct. Note that the Faultoutput signal remains latched until the fault condition is removed and the protection circuit is cleared.as explained under Clearing Protection Functions.Pin 2's selected function is ignored. Pin 2 should be connected to the ground of theexternal circuit.Front Panel Menu Reference SCPI CommandSelect System\IO\DigPort\Pins.Select pin 1, then Function, then Fault Out.In the Polarity field, select either Positive or Negative.To configure the Fault function:DIG:PIN1:FUNC FAULTo select the pin polarity:DIG:PIN1:POL POS4 Using the Advanced Power System154 Keysight N6900/N7900 Series Operating and Service Guide
