Agilent Technologies 3138A-00101 and above, 66000A manual Trigger Connections, Digital Connector

	Figure 3-3. Digital Connector
FLT Output	Used to indicate that a fault has occurred on one of the modules in the mainframe. Pins 1 and 2
(pins 1 and 2)	are the open-collector output of an optocoupler, with pin 1 the collector and pin 2 the emitter. When a
	fault has occurred, pin 1 is driven low with respect to pin 2 (negative-true).
INH Input	Used to shut down the outputs of all modules in the mainframe that have been enabled to respond to
(pin 3)	the remote inhibit function. Pin 3 is a high impedance input. The inhibit function is activated when this
	input is driven low (negative-true). This can be accomplished by shorting pin 3 to pin 4.
INH Common	Provides the common connection for the INH input.
(pin 4)

After you have finished making all wire connections, replace the mating plug in the connector.

Figure 3-4 shows two simple applications for the INH input. The first is a "panic switch" that applies the INH input signal to both mainframes, which shuts down the modules simultaneously in both mainframes. The second application uses the INH input signal to shut down modules in the main mainframe. In this case, the modules in the main mainframe must be programmed to generate an FLT signal upon receipt of the INH signal. The FLT signal generated by the modules in the main mainframe is then applied to the RI input of the auxiliary mainframe.

Note Software control of the RI function is described further in Chapter 5 of the module Programming Guide.

Trigger Connections

Trigger connections are made to the BNC connectors on the rear panel as shown in Figure 3-1. The electrical characteristics of the trigger connectors are described in Chapter 1. More information on the capabilities of the external triggers can be found in Chapter 5 of the module Programming Guide.

Trigger IN Allows negative-going external trigger signals to trigger one or more modules in the mainframe.

Trigger OUT Provides a negative-going wired-ORed pulse that indicates a trigger has occurred on one or more of the modules in the mainframe.

24Connections