forked from Archive/PX4-Autopilot
596 lines
14 KiB
C
596 lines
14 KiB
C
/****************************************************************************
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*
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* Copyright (C) 2012 PX4 Development Team. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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* 3. Neither the name PX4 nor the names of its contributors may be
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* used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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****************************************************************************/
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/**
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* @file registers.c
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*
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* Implementation of the PX4IO register space.
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*/
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#include <nuttx/config.h>
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#include <stdbool.h>
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#include <stdlib.h>
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#include <drivers/drv_hrt.h>
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#include "px4io.h"
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#include "protocol.h"
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static int registers_set_one(uint8_t page, uint8_t offset, uint16_t value);
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/**
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* PAGE 0
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*
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* Static configuration parameters.
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*/
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static const uint16_t r_page_config[] = {
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[PX4IO_P_CONFIG_PROTOCOL_VERSION] = 1, /* XXX hardcoded magic number */
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[PX4IO_P_CONFIG_SOFTWARE_VERSION] = 1, /* XXX hardcoded magic number */
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[PX4IO_P_CONFIG_BOOTLOADER_VERSION] = 3, /* XXX hardcoded magic number */
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[PX4IO_P_CONFIG_MAX_TRANSFER] = 64, /* XXX hardcoded magic number */
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[PX4IO_P_CONFIG_CONTROL_COUNT] = PX4IO_CONTROL_CHANNELS,
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[PX4IO_P_CONFIG_ACTUATOR_COUNT] = IO_SERVO_COUNT,
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[PX4IO_P_CONFIG_RC_INPUT_COUNT] = MAX_CONTROL_CHANNELS,
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[PX4IO_P_CONFIG_ADC_INPUT_COUNT] = ADC_CHANNEL_COUNT,
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[PX4IO_P_CONFIG_RELAY_COUNT] = PX4IO_RELAY_CHANNELS,
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};
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/**
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* PAGE 1
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*
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* Status values.
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*/
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uint16_t r_page_status[] = {
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[PX4IO_P_STATUS_FREEMEM] = 0,
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[PX4IO_P_STATUS_CPULOAD] = 0,
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[PX4IO_P_STATUS_FLAGS] = 0,
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[PX4IO_P_STATUS_ALARMS] = 0,
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[PX4IO_P_STATUS_VBATT] = 0,
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[PX4IO_P_STATUS_IBATT] = 0
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};
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/**
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* PAGE 2
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*
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* Post-mixed actuator values.
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*/
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uint16_t r_page_actuators[IO_SERVO_COUNT];
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/**
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* PAGE 3
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*
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* Servo PWM values
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*/
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uint16_t r_page_servos[IO_SERVO_COUNT];
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/**
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* PAGE 4
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*
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* Raw RC input
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*/
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uint16_t r_page_raw_rc_input[] =
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{
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[PX4IO_P_RAW_RC_COUNT] = 0,
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[PX4IO_P_RAW_RC_BASE ... (PX4IO_P_RAW_RC_BASE + MAX_CONTROL_CHANNELS)] = 0
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};
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/**
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* PAGE 5
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*
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* Scaled/routed RC input
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*/
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uint16_t r_page_rc_input[] = {
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[PX4IO_P_RC_VALID] = 0,
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[PX4IO_P_RC_BASE ... (PX4IO_P_RC_BASE + MAX_CONTROL_CHANNELS)] = 0
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};
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/**
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* PAGE 6
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*
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* Raw ADC input.
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*/
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uint16_t r_page_adc[ADC_CHANNEL_COUNT];
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/**
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* PAGE 100
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*
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* Setup registers
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*/
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volatile uint16_t r_page_setup[] =
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{
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[PX4IO_P_SETUP_FEATURES] = 0,
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[PX4IO_P_SETUP_ARMING] = 0,
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[PX4IO_P_SETUP_PWM_RATES] = 0,
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[PX4IO_P_SETUP_PWM_LOWRATE] = 50,
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[PX4IO_P_SETUP_PWM_HIGHRATE] = 200,
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[PX4IO_P_SETUP_RELAYS] = 0,
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[PX4IO_P_SETUP_VBATT_SCALE] = 10000,
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[PX4IO_P_SETUP_IBATT_SCALE] = 0,
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[PX4IO_P_SETUP_IBATT_BIAS] = 0,
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[PX4IO_P_SETUP_SET_DEBUG] = 0,
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};
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#define PX4IO_P_SETUP_FEATURES_VALID (0)
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#define PX4IO_P_SETUP_ARMING_VALID (PX4IO_P_SETUP_ARMING_ARM_OK | \
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PX4IO_P_SETUP_ARMING_MANUAL_OVERRIDE_OK | \
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PX4IO_P_SETUP_ARMING_INAIR_RESTART_OK)
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#define PX4IO_P_SETUP_RATES_VALID ((1 << IO_SERVO_COUNT) - 1)
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#define PX4IO_P_SETUP_RELAYS_VALID ((1 << PX4IO_RELAY_CHANNELS) - 1)
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/**
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* PAGE 101
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*
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* Control values from the FMU.
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*/
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volatile uint16_t r_page_controls[PX4IO_CONTROL_CHANNELS];
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/*
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* PAGE 102 does not have a buffer.
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*/
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/**
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* PAGE 103
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*
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* R/C channel input configuration.
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*/
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uint16_t r_page_rc_input_config[MAX_CONTROL_CHANNELS * PX4IO_P_RC_CONFIG_STRIDE];
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/* valid options */
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#define PX4IO_P_RC_CONFIG_OPTIONS_VALID (PX4IO_P_RC_CONFIG_OPTIONS_REVERSE | PX4IO_P_RC_CONFIG_OPTIONS_ENABLED)
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/*
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* PAGE 104 uses r_page_servos.
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*/
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/**
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* PAGE 105
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*
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* Failsafe servo PWM values
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*/
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uint16_t r_page_servo_failsafe[IO_SERVO_COUNT];
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void
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registers_set(uint8_t page, uint8_t offset, const uint16_t *values, unsigned num_values)
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{
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switch (page) {
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/* handle bulk controls input */
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case PX4IO_PAGE_CONTROLS:
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/* copy channel data */
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while ((offset < PX4IO_CONTROL_CHANNELS) && (num_values > 0)) {
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/* XXX range-check value? */
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r_page_controls[offset] = *values;
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offset++;
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num_values--;
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values++;
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}
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system_state.fmu_data_received_time = hrt_absolute_time();
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r_status_flags |= PX4IO_P_STATUS_FLAGS_FMU_OK;
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r_status_alarms &= ~PX4IO_P_STATUS_ALARMS_FMU_LOST;
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r_status_flags &= ~PX4IO_P_STATUS_FLAGS_RAW_PWM;
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break;
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/* handle raw PWM input */
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case PX4IO_PAGE_DIRECT_PWM:
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/* copy channel data */
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while ((offset < PX4IO_CONTROL_CHANNELS) && (num_values > 0)) {
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/* XXX range-check value? */
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r_page_servos[offset] = *values;
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offset++;
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num_values--;
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values++;
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}
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system_state.fmu_data_received_time = hrt_absolute_time();
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r_status_flags |= PX4IO_P_STATUS_FLAGS_FMU_OK | PX4IO_P_STATUS_FLAGS_RAW_PWM;
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break;
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/* handle setup for servo failsafe values */
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case PX4IO_PAGE_FAILSAFE_PWM:
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/* copy channel data */
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while ((offset < PX4IO_CONTROL_CHANNELS) && (num_values > 0)) {
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/* XXX range-check value? */
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r_page_servo_failsafe[offset] = *values;
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offset++;
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num_values--;
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values++;
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}
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break;
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/* handle text going to the mixer parser */
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case PX4IO_PAGE_MIXERLOAD:
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mixer_handle_text(values, num_values * sizeof(*values));
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break;
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default:
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/* avoid offset wrap */
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if ((offset + num_values) > 255)
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num_values = 255 - offset;
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/* iterate individual registers, set each in turn */
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while (num_values--) {
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if (registers_set_one(page, offset, *values))
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break;
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offset++;
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values++;
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}
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}
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}
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static int
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registers_set_one(uint8_t page, uint8_t offset, uint16_t value)
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{
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switch (page) {
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case PX4IO_PAGE_STATUS:
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switch (offset) {
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case PX4IO_P_STATUS_ALARMS:
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/* clear bits being written */
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r_status_alarms &= ~value;
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break;
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case PX4IO_P_STATUS_FLAGS:
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/*
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* Allow FMU override of arming state (to allow in-air restores),
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* but only if the arming state is not in sync on the IO side.
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*/
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if (!(r_status_flags & PX4IO_P_STATUS_FLAGS_ARM_SYNC)) {
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r_status_flags = value;
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}
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break;
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default:
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/* just ignore writes to other registers in this page */
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break;
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}
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break;
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case PX4IO_PAGE_SETUP:
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switch (offset) {
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case PX4IO_P_SETUP_FEATURES:
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value &= PX4IO_P_SETUP_FEATURES_VALID;
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r_setup_features = value;
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/* no implemented feature selection at this point */
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break;
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case PX4IO_P_SETUP_ARMING:
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value &= PX4IO_P_SETUP_ARMING_VALID;
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/*
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* Update arming state - disarm if no longer OK.
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* This builds on the requirement that the FMU driver
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* asks about the FMU arming state on initialization,
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* so that an in-air reset of FMU can not lead to a
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* lockup of the IO arming state.
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*/
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if ((r_setup_arming & PX4IO_P_SETUP_ARMING_ARM_OK) && !(value & PX4IO_P_SETUP_ARMING_ARM_OK)) {
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r_status_flags &= ~PX4IO_P_STATUS_FLAGS_ARMED;
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}
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r_setup_arming = value;
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break;
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case PX4IO_P_SETUP_PWM_RATES:
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value &= PX4IO_P_SETUP_RATES_VALID;
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r_setup_pwm_rates = value;
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/* XXX re-configure timers */
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break;
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case PX4IO_P_SETUP_PWM_LOWRATE:
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if (value < 50)
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value = 50;
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if (value > 400)
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value = 400;
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r_setup_pwm_lowrate = value;
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/* XXX re-configure timers */
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break;
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case PX4IO_P_SETUP_PWM_HIGHRATE:
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if (value < 50)
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value = 50;
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if (value > 400)
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value = 400;
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r_setup_pwm_highrate = value;
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/* XXX re-configure timers */
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break;
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case PX4IO_P_SETUP_RELAYS:
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value &= PX4IO_P_SETUP_RELAYS_VALID;
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r_setup_relays = value;
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POWER_RELAY1(value & (1 << 0) ? 1 : 0);
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POWER_RELAY2(value & (1 << 1) ? 1 : 0);
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POWER_ACC1(value & (1 << 2) ? 1 : 0);
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POWER_ACC2(value & (1 << 3) ? 1 : 0);
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break;
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case PX4IO_P_SETUP_SET_DEBUG:
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r_page_setup[PX4IO_P_SETUP_SET_DEBUG] = value;
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isr_debug(0, "set debug %u\n", (unsigned)r_page_setup[PX4IO_P_SETUP_SET_DEBUG]);
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break;
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default:
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return -1;
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}
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break;
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case PX4IO_PAGE_RC_CONFIG: {
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/* do not allow a RC config change while fully armed */
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if (/* FMU is armed */ (r_setup_arming & PX4IO_P_SETUP_ARMING_ARM_OK) &&
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/* IO is armed */ (r_status_flags & PX4IO_P_STATUS_FLAGS_ARMED)) {
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break;
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}
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unsigned channel = offset / PX4IO_P_RC_CONFIG_STRIDE;
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unsigned index = offset - channel * PX4IO_P_RC_CONFIG_STRIDE;
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uint16_t *conf = &r_page_rc_input_config[channel * PX4IO_P_RC_CONFIG_STRIDE];
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if (channel >= MAX_CONTROL_CHANNELS)
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return -1;
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/* disable the channel until we have a chance to sanity-check it */
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conf[PX4IO_P_RC_CONFIG_OPTIONS] &= PX4IO_P_RC_CONFIG_OPTIONS_ENABLED;
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switch (index) {
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case PX4IO_P_RC_CONFIG_MIN:
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case PX4IO_P_RC_CONFIG_CENTER:
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case PX4IO_P_RC_CONFIG_MAX:
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case PX4IO_P_RC_CONFIG_DEADZONE:
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case PX4IO_P_RC_CONFIG_ASSIGNMENT:
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conf[index] = value;
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break;
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case PX4IO_P_RC_CONFIG_OPTIONS:
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value &= PX4IO_P_RC_CONFIG_OPTIONS_VALID;
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r_status_flags |= PX4IO_P_STATUS_FLAGS_INIT_OK;
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/* set all options except the enabled option */
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conf[index] = value & ~PX4IO_P_RC_CONFIG_OPTIONS_ENABLED;
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/* should the channel be enabled? */
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/* this option is normally set last */
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if (value & PX4IO_P_RC_CONFIG_OPTIONS_ENABLED) {
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uint8_t count = 0;
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/* assert min..center..max ordering */
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if (conf[PX4IO_P_RC_CONFIG_MIN] < 500) {
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count++;
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}
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if (conf[PX4IO_P_RC_CONFIG_MAX] > 2500) {
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count++;
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}
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if (conf[PX4IO_P_RC_CONFIG_CENTER] < conf[PX4IO_P_RC_CONFIG_MIN]) {
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count++;
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}
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if (conf[PX4IO_P_RC_CONFIG_CENTER] > conf[PX4IO_P_RC_CONFIG_MAX]) {
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count++;
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}
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/* assert deadzone is sane */
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if (conf[PX4IO_P_RC_CONFIG_DEADZONE] > 500) {
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count++;
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}
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// The following check isn't needed as constraint checks in controls.c will catch this.
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//if (conf[PX4IO_P_RC_CONFIG_MIN] > (conf[PX4IO_P_RC_CONFIG_CENTER] - conf[PX4IO_P_RC_CONFIG_DEADZONE])) {
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// count++;
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//}
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//if (conf[PX4IO_P_RC_CONFIG_MAX] < (conf[PX4IO_P_RC_CONFIG_CENTER] + conf[PX4IO_P_RC_CONFIG_DEADZONE])) {
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// count++;
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//}
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if (conf[PX4IO_P_RC_CONFIG_ASSIGNMENT] >= MAX_CONTROL_CHANNELS) {
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count++;
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}
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/* sanity checks pass, enable channel */
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if (count) {
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isr_debug(0, "ERROR: %d config error(s) for RC%d.\n", count, (channel + 1));
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r_status_flags &= ~PX4IO_P_STATUS_FLAGS_INIT_OK;
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} else {
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conf[index] |= PX4IO_P_RC_CONFIG_OPTIONS_ENABLED;
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}
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}
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break;
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/* inner switch: case PX4IO_P_RC_CONFIG_OPTIONS */
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}
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break;
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/* case PX4IO_RC_PAGE_CONFIG */
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}
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default:
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return -1;
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}
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return 0;
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}
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uint8_t last_page;
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uint8_t last_offset;
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int
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registers_get(uint8_t page, uint8_t offset, uint16_t **values, unsigned *num_values)
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{
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#define SELECT_PAGE(_page_name) \
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do { \
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*values = &_page_name[0]; \
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*num_values = sizeof(_page_name) / sizeof(_page_name[0]); \
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} while(0)
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switch (page) {
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/*
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* Handle pages that are updated dynamically at read time.
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*/
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case PX4IO_PAGE_STATUS:
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/* PX4IO_P_STATUS_FREEMEM */
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{
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struct mallinfo minfo = mallinfo();
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r_page_status[PX4IO_P_STATUS_FREEMEM] = minfo.fordblks;
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}
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/* XXX PX4IO_P_STATUS_CPULOAD */
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/* PX4IO_P_STATUS_FLAGS maintained externally */
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/* PX4IO_P_STATUS_ALARMS maintained externally */
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/* PX4IO_P_STATUS_VBATT */
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{
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/*
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* Coefficients here derived by measurement of the 5-16V
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* range on one unit:
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*
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* V counts
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* 5 1001
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* 6 1219
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* 7 1436
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* 8 1653
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* 9 1870
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* 10 2086
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* 11 2303
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* 12 2522
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* 13 2738
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* 14 2956
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* 15 3172
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* 16 3389
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*
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* slope = 0.0046067
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* intercept = 0.3863
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*
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* Intercept corrected for best results @ 12V.
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*/
|
|
unsigned counts = adc_measure(ADC_VBATT);
|
|
unsigned mV = (4150 + (counts * 46)) / 10 - 200;
|
|
unsigned corrected = (mV * r_page_setup[PX4IO_P_SETUP_VBATT_SCALE]) / 10000;
|
|
|
|
r_page_status[PX4IO_P_STATUS_VBATT] = corrected;
|
|
}
|
|
|
|
/* PX4IO_P_STATUS_IBATT */
|
|
{
|
|
unsigned counts = adc_measure(ADC_VBATT);
|
|
unsigned scaled = (counts * r_page_setup[PX4IO_P_SETUP_IBATT_SCALE]) / 10000;
|
|
int corrected = scaled + REG_TO_SIGNED(r_page_setup[PX4IO_P_SETUP_IBATT_BIAS]);
|
|
if (corrected < 0)
|
|
corrected = 0;
|
|
r_page_status[PX4IO_P_STATUS_IBATT] = corrected;
|
|
}
|
|
|
|
SELECT_PAGE(r_page_status);
|
|
break;
|
|
|
|
case PX4IO_PAGE_RAW_ADC_INPUT:
|
|
r_page_adc[0] = adc_measure(ADC_VBATT);
|
|
r_page_adc[1] = adc_measure(ADC_IN5);
|
|
|
|
SELECT_PAGE(r_page_adc);
|
|
break;
|
|
|
|
/*
|
|
* Pages that are just a straight read of the register state.
|
|
*/
|
|
|
|
/* status pages */
|
|
case PX4IO_PAGE_CONFIG:
|
|
SELECT_PAGE(r_page_config);
|
|
break;
|
|
case PX4IO_PAGE_ACTUATORS:
|
|
SELECT_PAGE(r_page_actuators);
|
|
break;
|
|
case PX4IO_PAGE_SERVOS:
|
|
SELECT_PAGE(r_page_servos);
|
|
break;
|
|
case PX4IO_PAGE_RAW_RC_INPUT:
|
|
SELECT_PAGE(r_page_raw_rc_input);
|
|
break;
|
|
case PX4IO_PAGE_RC_INPUT:
|
|
SELECT_PAGE(r_page_rc_input);
|
|
break;
|
|
|
|
/* readback of input pages */
|
|
case PX4IO_PAGE_SETUP:
|
|
SELECT_PAGE(r_page_setup);
|
|
break;
|
|
case PX4IO_PAGE_CONTROLS:
|
|
SELECT_PAGE(r_page_controls);
|
|
break;
|
|
case PX4IO_PAGE_RC_CONFIG:
|
|
SELECT_PAGE(r_page_rc_input_config);
|
|
break;
|
|
case PX4IO_PAGE_DIRECT_PWM:
|
|
SELECT_PAGE(r_page_servos);
|
|
break;
|
|
case PX4IO_PAGE_FAILSAFE_PWM:
|
|
SELECT_PAGE(r_page_servo_failsafe);
|
|
break;
|
|
|
|
default:
|
|
return -1;
|
|
}
|
|
|
|
#undef SELECT_PAGE
|
|
#undef COPY_PAGE
|
|
|
|
last_page = page;
|
|
last_offset = offset;
|
|
|
|
/* if the offset is at or beyond the end of the page, we have no data */
|
|
if (offset >= *num_values)
|
|
return -1;
|
|
|
|
/* correct the data pointer and count for the offset */
|
|
*values += offset;
|
|
*num_values -= offset;
|
|
|
|
return 0;
|
|
}
|