In order to create a noise gate in SigmaStudio, use the Dynamics Processors cells. An RMS-detect type will work best for audio applications. Place the dynamics processor cell in the project and leave the curve in its default state.
After compilation, move the bottom-most point on the curve slightly down. The capture window will display a parameter update write sequence.
The top line (first write) is the gain table. It should have 136 bytes. This table shows the linear gain applied to inputs starting at -90dB(RMS) and incrementing 3dB each address. Since the compressor is the only processing algorithm in this example project, the first point in the table at address 0 aligns with -90dB.
In order to create a noise gate, the values for all gain table points below the gate threshold should be set to 0x00, 0x00, 0x00, 0x00. In order to do this, use the sequencer. Start by creating a write at address 0 (the point for -90dB), and set the value to 0x00 0x00 0x00 0x00.
In this example, the threshold has been set to -81dB. Any audio input below -81dB will cause the output to drop to 0.
In order to implement the changes on your hardware, click the Download Mode to Hardware button.
The timing of the gate can be tweaked by changing the timing parameters of the dynamics processor cell.