ardupilot/libraries/AP_IOMCU/iofirmware/ioprotocol.h

/*
  common protocol definitions between AP_IOMCU and iofirmware
 */

#define PKT_MAX_REGS 32
#define IOMCU_MAX_CHANNELS 16

//#define IOMCU_DEBUG

struct PACKED IOPacket {
    uint8_t 	count:6;
    uint8_t 	code:2;
    uint8_t 	crc;
    uint8_t 	page;
    uint8_t 	offset;
    uint16_t	regs[PKT_MAX_REGS];

    // get packet size in bytes
    uint8_t get_size(void) const
    {
        return count*2 + 4;
    }
};

/*
  values for pkt.code
 */
enum iocode {
    // read types
    CODE_READ = 0,
    CODE_WRITE = 1,

    // reply codes
    CODE_SUCCESS = 0,
    CODE_CORRUPT = 1,
    CODE_ERROR = 2
};

// IO pages
enum iopage {
    PAGE_CONFIG = 0,
    PAGE_STATUS = 1,
    PAGE_ACTUATORS = 2,
    PAGE_SERVOS = 3,
    PAGE_RAW_RCIN = 4,
    PAGE_RCIN = 5,
    PAGE_RAW_ADC = 6,
    PAGE_PWM_INFO = 7,
    PAGE_SETUP = 50,
    PAGE_DIRECT_PWM = 54,
    PAGE_FAILSAFE_PWM = 55,
    PAGE_SAFETY_PWM = 108,
    PAGE_MIXING = 200,
};

// setup page registers
#define PAGE_REG_SETUP_FEATURES	0
#define P_SETUP_FEATURES_SBUS1_OUT	1
#define P_SETUP_FEATURES_SBUS2_OUT	2
#define P_SETUP_FEATURES_PWM_RSSI   4
#define P_SETUP_FEATURES_ADC_RSSI   8
#define P_SETUP_FEATURES_ONESHOT   16
#define P_SETUP_FEATURES_BRUSHED   32

#define PAGE_REG_SETUP_ARMING 1
#define P_SETUP_ARMING_IO_ARM_OK (1<<0)
#define P_SETUP_ARMING_FMU_ARMED (1<<1)
#define P_SETUP_ARMING_RC_HANDLING_DISABLED (1<<6)
#define P_SETUP_ARMING_SAFETY_DISABLE_ON	(1 << 11) // disable use of safety button for safety off->on
#define P_SETUP_ARMING_SAFETY_DISABLE_OFF	(1 << 12) // disable use of safety button for safety on->off

#define PAGE_REG_SETUP_PWM_RATE_MASK 2
#define PAGE_REG_SETUP_DEFAULTRATE   3
#define PAGE_REG_SETUP_ALTRATE       4
#define PAGE_REG_SETUP_REBOOT_BL    10
#define PAGE_REG_SETUP_CRC			11
#define PAGE_REG_SETUP_SBUS_RATE    19
#define PAGE_REG_SETUP_IGNORE_SAFETY 20 /* bitmask of surfaces to ignore the safety status */
#define PAGE_REG_SETUP_HEATER_DUTY_CYCLE 21

// config page registers
#define PAGE_CONFIG_PROTOCOL_VERSION 0
#define IOMCU_PROTOCOL_VERSION       10

// magic value for rebooting to bootloader
#define REBOOT_BL_MAGIC 14662

#define PAGE_REG_SETUP_FORCE_SAFETY_OFF 12
#define PAGE_REG_SETUP_FORCE_SAFETY_ON  14
#define FORCE_SAFETY_MAGIC 22027

struct PACKED page_config {
    uint16_t protocol_version;
};

struct PACKED page_reg_status {
    uint16_t freemem;
    uint16_t cpuload;

    // status flags
    uint16_t flag_outputs_armed:1;
    uint16_t flag_override:1;
    uint16_t flag_rc_ok:1;
    uint16_t flag_rc_ppm:1;
    uint16_t flag_rc_dsm:1;
    uint16_t flag_rc_sbus:1;
    uint16_t flag_fmu_ok:1;
    uint16_t flag_raw_pwm:1;
    uint16_t flag_mixer_ok:1;
    uint16_t flag_arm_sync:1;
    uint16_t flag_init_ok:1;
    uint16_t flag_failsafe:1;
    uint16_t flag_safety_off:1;
    uint16_t flag_fmu_initialised:1;
    uint16_t flag_rc_st24:1;
    uint16_t flag_rc_sumd_srxl:1;

    uint16_t alarms;
    uint16_t vbatt;
    uint16_t ibatt;
    uint16_t vservo;
    uint16_t vrssi;
    uint16_t prssi;
};

struct PACKED page_rc_input {
    uint16_t count;
    uint16_t flags_frame_drop:1;
    uint16_t flags_failsafe:1;
    uint16_t flags_dsm11:1;
    uint16_t flags_mapping_ok:1;
    uint16_t flags_rc_ok:1;
    uint16_t flags_unused:11;
    uint16_t nrssi;
    uint16_t data;
    uint16_t frame_count;
    uint16_t lost_frame_count;
    uint16_t pwm[IOMCU_MAX_CHANNELS];
    uint16_t last_frame_count;
    uint32_t last_input_us;
};

/*
  data for mixing on FMU failsafe
 */
struct PACKED page_mixing {
    uint16_t servo_min[IOMCU_MAX_CHANNELS];
    uint16_t servo_max[IOMCU_MAX_CHANNELS];
    uint16_t servo_trim[IOMCU_MAX_CHANNELS];
    uint8_t servo_function[IOMCU_MAX_CHANNELS];
    uint8_t servo_reversed[IOMCU_MAX_CHANNELS];

    // RC input arrays are in AETR order
    uint16_t rc_min[4];
    uint16_t rc_max[4];
    uint16_t rc_trim[4];
    uint8_t rc_reversed[IOMCU_MAX_CHANNELS];
    uint8_t rc_channel[4];

    // gain for elevon and vtail mixing, x1000
    uint16_t mixing_gain;

    // channel which when high forces mixer
    int8_t rc_chan_override;

    // is the throttle an angle input?
    uint8_t throttle_is_angle;

    // mask of channels which are pure manual in override
    uint16_t manual_rc_mask;

    // enabled needs to be 1 to enable mixing
    uint8_t enabled;

    uint8_t pad; // pad to even size
};