Software defined triggers is essentially what is meant with streaming readout. I try to avoid to use this, because it confused the heck out of people in the NP

Software defined triggers is essentially what is meant with streaming readout. I try to avoid to use this, because it confused the heck out of people in the NP community. I prefer "software data filter", I think that's more accurate anyway, as the software trigger doesn't actually trigger anything anymore (in the sense of a QDC gate, for example), but just marks which data should be passed on and which should be dropped. HEP is a lot further along on this transition, but I can tell you that virtually all NP experiments use either a standard hardware trigger, or at least a fixed latency hardware signal to readout from a (small length) digital or often analog buffer filled from a continuously converting ADC. One of the new detectors in SBS (one of the detectors in Hall A of Jefferson Lab) for example is read out with APV25 chips -- they need a fixed latency, electronic trigger signal. (Disclaimer: I was a PI of eRD23: Streaming readout for EIC)