Fresh import of the PX4 firmware sources.

1 files changed, 104 insertions, 0 deletions

diff --git a/apps/px4io/safety.c b/apps/px4io/safety.c
new file mode 100644
index 000000000..895c33806
--- /dev/null
+++ b/apps/px4io/safety.c
@@ -0,0 +1,104 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *
+ * 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 Safety button logic.
+  */
+
+#include <nuttx/config.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <debug.h>
+#include <stdlib.h>
+#include <errno.h>
+
+#include <nuttx/clock.h>
+
+#include <arch/board/up_boardinitialize.h>
+#include <arch/board/drv_gpio.h>
+#include <arch/board/drv_ppm_input.h>
+#include <arch/board/up_hrt.h>
+
+#include "px4io.h"
+
+static struct hrt_call arming_call;
+
+/*
+ * Count the number of times in a row that we see the arming button
+ * held down.
+ */
+static unsigned arm_counter;
+#define ARM_COUNTER_THRESHOLD	10
+
+static bool safety_led_state;
+
+static void safety_check_button(void *arg);
+
+void
+safety_init(void)
+{
+	/* arrange for the button handler to be called at 10Hz */
+	hrt_call_every(&arming_call, 1000, 100000, safety_check_button, NULL);
+}
+
+static void
+safety_check_button(void *arg)
+{
+	/* 
+	 * Debounce the safety button, change state if it has been held for long enough.
+	 *
+	 * Ignore the button if FMU has not said it's OK to arm yet.
+	 */
+	if (BUTTON_SAFETY && system_state.arm_ok) {
+		if (arm_counter < ARM_COUNTER_THRESHOLD) {
+			arm_counter++;
+		} else if (arm_counter == ARM_COUNTER_THRESHOLD) {
+			/* change our armed state and notify the FMU */
+			system_state.armed = !system_state.armed;
+			arm_counter++;
+			system_state.fmu_report_due = true;
+		}
+	} else {
+		arm_counter = 0;
+	}
+
+	/* when armed, toggle the LED; when safe, leave it on */
+	if (system_state.armed) {
+		safety_led_state = !safety_led_state;
+	} else {
+		safety_led_state = true;
+	}
+	LED_SAFETY(safety_led_state);
+}