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author | px4dev <px4@purgatory.org> | 2012-08-04 15:12:36 -0700 |
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committer | px4dev <px4@purgatory.org> | 2012-08-04 15:12:36 -0700 |
commit | 8a365179eafdf3aea98e60ab9f5882b200d4c759 (patch) | |
tree | 4f38d6d4cd80bd0b6e22e2bb534c3f117ce44e56 /apps/px4io/mixer.c | |
download | px4-firmware-8a365179eafdf3aea98e60ab9f5882b200d4c759.tar.gz px4-firmware-8a365179eafdf3aea98e60ab9f5882b200d4c759.tar.bz2 px4-firmware-8a365179eafdf3aea98e60ab9f5882b200d4c759.zip |
Fresh import of the PX4 firmware sources.
Diffstat (limited to 'apps/px4io/mixer.c')
-rw-r--r-- | apps/px4io/mixer.c | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/apps/px4io/mixer.c b/apps/px4io/mixer.c new file mode 100644 index 000000000..9dc1fdcba --- /dev/null +++ b/apps/px4io/mixer.c @@ -0,0 +1,245 @@ +/**************************************************************************** + * + * 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 Control channel input/output mixer and failsafe. + */ + +#include <nuttx/config.h> +#include <nuttx/arch.h> + +#include <sys/types.h> +#include <stdbool.h> + +#include <assert.h> +#include <errno.h> +#include <fcntl.h> + +#include <arch/board/drv_ppm_input.h> +#include <arch/board/drv_pwm_servo.h> +#include <arch/board/up_hrt.h> + +#include "px4io.h" + +#ifdef CONFIG_DISABLE_MQUEUE +# error Mixer requires message queues - set CONFIG_DISABLE_MQUEUE=n and try again +#endif + +static mqd_t input_queue; + +/* + * Count of periodic calls in which we have no data. + */ +static unsigned mixer_input_drops; +#define MIXER_INPUT_DROP_LIMIT 10 + +/* + * Count of periodic calls in which we have no FMU input. + */ +static unsigned fmu_input_drops; +#define FMU_INPUT_DROP_LIMIT 10 + +/* + * HRT periodic call used to check for control input data. + */ +static struct hrt_call mixer_input_call; + +/* + * Mixer periodic tick. + */ +static void mixer_tick(void *arg); + +/* + * Collect RC input data from the controller source(s). + */ +static void mixer_get_rc_input(void); + +/* + * Update a mixer based on the current control signals. + */ +static void mixer_update(int mixer, uint16_t *inputs, int input_count); + +/* servo driver handle */ +int mixer_servo_fd; + +/* current servo arm/disarm state */ +bool mixer_servos_armed; + +/* + * Each mixer consumes a set of inputs and produces a single output. + */ +struct mixer { + uint16_t current_value; + /* XXX more config here */ +} mixers[IO_SERVO_COUNT]; + +int +mixer_init(const char *mq_name) +{ + /* open the control input queue; this should always exist */ + input_queue = mq_open(mq_name, O_RDONLY | O_NONBLOCK); + ASSERTCODE((input_queue >= 0), A_INPUTQ_OPEN_FAIL); + + /* open the servo driver */ + mixer_servo_fd = open("/dev/pwm_servo", O_WRONLY); + ASSERTCODE((mixer_servo_fd >= 0), A_SERVO_OPEN_FAIL); + + /* look for control data at 50Hz */ + hrt_call_every(&mixer_input_call, 1000, 20000, mixer_tick, NULL); + + return 0; +} + +static void +mixer_tick(void *arg) +{ + uint16_t *control_values; + int control_count; + int i; + bool should_arm; + + /* + * Start by looking for R/C control inputs. + * This updates system_state with any control inputs received. + */ + mixer_get_rc_input(); + + /* + * Decide which set of inputs we're using. + */ + if (system_state.mixer_use_fmu) { + /* we have recent control data from the FMU */ + control_count = PX4IO_OUTPUT_CHANNELS; + control_values = &system_state.fmu_channel_data[0]; + + /* check that we are receiving fresh data from the FMU */ + if (!system_state.fmu_data_received) { + fmu_input_drops++; + + /* too many frames without FMU input, time to go to failsafe */ + if (fmu_input_drops >= FMU_INPUT_DROP_LIMIT) { + system_state.mixer_use_fmu = false; + } + } else { + fmu_input_drops = 0; + system_state.fmu_data_received = false; + } + + } else if (system_state.rc_channels > 0) { + /* we have control data from an R/C input */ + control_count = system_state.rc_channels; + control_values = &system_state.rc_channel_data[0]; + + } else { + /* we have no control input */ + control_count = 0; + } + + /* + * Tickle each mixer, if we have control data. + */ + if (control_count > 0) { + for (i = 0; i < PX4IO_OUTPUT_CHANNELS; i++) { + mixer_update(i, control_values, control_count); + + /* + * If we are armed, update the servo output. + */ + if (system_state.armed) + ioctl(mixer_servo_fd, PWM_SERVO_SET(i), mixers[i].current_value); + } + + } + + /* + * Decide whether the servos should be armed right now. + */ + should_arm = system_state.armed && (control_count > 0); + if (should_arm && !mixer_servos_armed) { + /* need to arm, but not armed */ + ioctl(mixer_servo_fd, PWM_SERVO_ARM, 0); + mixer_servos_armed = true; + + } else if (!should_arm && mixer_servos_armed) { + /* armed but need to disarm*/ + ioctl(mixer_servo_fd, PWM_SERVO_DISARM, 0); + mixer_servos_armed = false; + } +} + +static void +mixer_get_rc_input(void) +{ + ssize_t len; + + /* + * Pull channel data from the message queue into the system state structure. + * + */ + len = mq_receive(input_queue, &system_state.rc_channel_data, sizeof(system_state.rc_channel_data), NULL); + + /* + * If we have data, update the count and status. + */ + if (len > 0) { + system_state.rc_channels = len / sizeof(system_state.rc_channel_data[0]); + mixer_input_drops = 0; + + system_state.fmu_report_due = true; + } else { + /* + * No data; count the 'frame drops' and once we hit the limit + * assume that we have lost input. + */ + if (mixer_input_drops < MIXER_INPUT_DROP_LIMIT) { + mixer_input_drops++; + + /* if we hit the limit, stop pretending we have input and let the FMU know */ + if (mixer_input_drops == MIXER_INPUT_DROP_LIMIT) { + system_state.rc_channels = 0; + system_state.fmu_report_due = true; + } + } + } +} + +static void +mixer_update(int mixer, uint16_t *inputs, int input_count) +{ + /* simple passthrough for now */ + if (mixer < input_count) { + mixers[mixer].current_value = inputs[mixer]; + } else { + mixers[mixer].current_value = 0; + } +} |