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Triggered_Burst: Event-Triggered Burst
When an event-triggered macro detects a key press, sound card input signal, external digital state change, or external DC level change, it invokes the Trig_Target macro, which by default invokes this Triggered_Burst macro.
This indirect operation means you only need to replace one line in Trig_Target to enable any of the trigger macros to use it. Triggered_Burst was chosen as the default because it demonstrates event triggering, but it's also a useful macro on its own.
Triggered_Burst automatically loads the Burst_5ms_X2.GEN Generator setup each time it is run. This is a good demo, but you can create your own burst setup to meet your particular needs, which Triggered_Burst can use instead. Triggered_Burst assumes the burst will be generated on Left Stream 0, so you should be sure to use that for your own burst setup.
You can change the A.LoadGEN="Burst_5ms_X2" line to auto-load your own setup, or put a semicolon at the start of the line to disable the auto-load and load manually before use.
As written, Burst_5ms_X2.GEN creates two 5 ms bursts separated by a 3 ms gap, and repeats this every second.
Triggered_Burst modifies the burst parameters of the loaded setup (but not the .GEN file itself) to eliminate automatic repetition by setting a very long Train Cycle in the Burst Dialog. With the default Burst_5ms_X2.GEN this will result in a single instance of the two bursts for each triggering event.
A non-burst setup, such as a continuous tone, will not be converted to a burst by Triggered_Burst.
The macro uses normal level-based triggering with the Left Stream 0 generator output as the trigger source. The trigger level is set to 20% of full scale; this is a compromise, intended to catch the waveform peak of a recorded sound, while ignoring any leading noise. Negative trigger delay is then used to show the build-up before the trigger point.
Likewise, with a regular generated waveform that has a slow rise time, the 20% trigger level may come well after the nominal starting point. You can set a larger negative delay to see more of the start, or set a lower trigger level.
;<Help=H492B A.LoadGEN="Burst_5ms_X2" ;Change or delete as needed Ch=0 ;L.0. Stream TrigSrc=LO ;Left Out trigger source TrigSngl=0 ;Disable Single-frame operation TrigMode=Norm ;Normal level-based trigger TrigLevel=20 ;Trigger at 20% of full scale Trig=1 ;Trigger on SmplSec=1 ;Force seconds units TrigDelay=-5m ;Display starts 5 ms before trigger Ch.TrainLag=150m ;Wait for sync restart if Input active Ch.TrainCycle=5G ;Set maximum delay before next burst TrigHold=Ch.TrainCount * Ch.BurstCycle ;No re-trig during burst Gen=1 ;Start the Generator
See also Macro Examples and Mini-Apps
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