Software Triggers

Software triggers occur when a software command starts the acquisition of posttrigger data. When you call Initiate Acquisition the digitizer starts acquiring pretrigger data and continues to do so until you call Send SW Trigger. The digitizer continues to store posttrigger samples after the software trigger, so you still need to wait for the acquisition to complete after the trigger. You can do this by setting the timeout parameter in a Fetch function to a positive value. You cannot use a Read function in conjunction with software triggering; you must use Initiate Acquisition followed by one of the Fetch functions. The following figure shows the programming flow using software trigger functions.