The triggering subsystem is used to start and stop analog input sampling. This is a new generalized triggering system. Please refer to Trigger Configuration and Trigger Start Delay Registers for further details. 

The Analog Input General Configuration Register bit nSGATE is used to enable triggering subsystem use. The nSGATE bit is required in order to support classic modes without special configuration. 

Further, the triggering subsystem must be enabled in order for it to function. 

There are three start triggering sequences:

1. Start trigger source --> Analog Input Sampling Begins
2. Start trigger source --> Trigger Delay --> Analog Input Sampling Begins
3. Start trigger source --> Start Trigger Synchronization source --> Trigger Delay -- > Analog Input Sampling Begins.

Analog input sampling is stopped upon a valid End/Stop Trigger Source event. 

What is the purpose of the triggering subsystem? It allows precise control as to when analog input sampling can occur. It is possible to synchronize sampling to 60Hz line source or whatever is chosen. It is possible to configure the STX104 to trigger on an event and accumulate N-samples and then stop sampling. 

The diagrams below illustrate how sample timing is affected by the SAIFTTS bit found in the Analog Input General Configuration Register. 

Trigger Configuration

Analog Inputs