Why doesn't the duty cycle of EMC2xxx reach 100% (KICK) during the spin-up routine?

Make sure that the KICK configuration is set. Spin-up is applicable when the TACH falls below the fan valid TACH COUNT. It is possible that the TACH is above the valid TACH COUNT that's why the spin-up routine is not seen. If you need to increase the rise time of the TACH, you can configure the gain of the PID.

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