Use defines instead of hardcoded magic values for maximum number of output channels and rpm filter time constant

src/drivers/rpm_capture/RPMCapture.cpp

@@ -59,7 +59,7 @@ bool RPMCapture::init()
 {
 	bool success = false;
 
-	for (unsigned i = 0; i < 16; ++i) {
+	for (unsigned i = 0; i < PWM_OUTPUT_MAX_CHANNELS; ++i) {
 		char param_name[17];
 		snprintf(param_name, sizeof(param_name), "%s_%s%d", PARAM_PREFIX, "FUNC", i + 1);
 		param_t function_handle = param_find(param_name);
@@ -138,7 +138,7 @@ void RPMCapture::Run()
 		// Don't update RPM filter with outliers
 		const float dt = math::min((now - _timestamp_last_update) * 1e-6f, 1.f);
 		_timestamp_last_update = now;
-		_rpm_filter.setParameters(dt, 0.5f);
+		_rpm_filter.setParameters(dt, RPM_FILTER_TIME_CONSTANT);
 		_rpm_filter.update(_rpm_median_filter.apply(rpm_raw));
 	}
 

src/drivers/rpm_capture/RPMCapture.hpp

@@ -72,6 +72,7 @@ public:
 private:
 	static constexpr hrt_abstime RPM_PULSE_TIMEOUT = 1_s;
 	static constexpr float RPM_MAX_VALUE = 50e3f;
+	static constexpr float RPM_FILTER_TIME_CONSTANT = .5f;
 
 	void Run() override;