In the SDK sample, this mode works as follows:

1. Model support is checked, then DRTECH_ExtRunSemiDynamicMode(1) is called.
2. The FPS is set (DRTECH_ExtSetFps). The exposure window and frame counter are not used, and hardware averaging is disabled.
3. DRTECH_StartSoftwareTrigger starts a continuous stream rather than a fixed-length sequence.
4. Each frame arrives through the same XcfReceived callback and is displayed immediately. The software trigger counter callback is ignored.
5. The stream is stopped only by DRTECH_StopSoftwareTrigger.

The mode status, current FPS, and maximum FPS are reported through the IDC_SEMI_DYNAMIC_MODE (0x1132) callback.