Moved PWM ramp to systemlib

1 files changed, 79 insertions, 0 deletions

diff --git a/src/modules/systemlib/pwm_limit/pwm_limit.h b/src/modules/systemlib/pwm_limit/pwm_limit.h
new file mode 100644
index 000000000..f8c6370e8
--- /dev/null
+++ b/src/modules/systemlib/pwm_limit/pwm_limit.h
@@ -0,0 +1,79 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2013 PX4 Development Team. All rights reserved.
+ *   Author: Julian Oes <joes@student.ethz.ch>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file pwm_limit.h
+ *
+ * Lib to limit PWM output
+ *
+ * @author Julian Oes <joes@student.ethz.ch>
+ */
+
+#ifndef PWM_LIMIT_H_
+#define PWM_LIMIT_H_
+
+#include <stdint.h>
+#include <stdbool.h>
+
+__BEGIN_DECLS
+
+/*
+ * time for the ESCs to initialize
+ * (this is not actually needed if PWM is sent right after boot)
+ */
+#define INIT_TIME_US 500000
+/*
+ * time to slowly ramp up the ESCs
+ */
+#define RAMP_TIME_US 2500000
+
+typedef struct {
+	enum {
+		LIMIT_STATE_OFF = 0,
+		LIMIT_STATE_INIT,
+		LIMIT_STATE_RAMP,
+		LIMIT_STATE_ON
+	} state;
+	uint64_t time_armed;
+	unsigned nchannels;
+} pwm_limit_t;
+
+__EXPORT void pwm_limit_init(pwm_limit_t *limit);
+
+__EXPORT void pwm_limit_calc(const bool armed, const uint16_t *disarmed_pwm, const uint16_t *min_pwm, const uint16_t *max_pwm, const float *output_requested, uint16_t *effective_pwm, pwm_limit_t *limit);
+
+
+__END_DECLS
+
+#endif /* PWM_LIMIT_H_ */