Line data    Source code

       1             : /*
       2             :  * This file is free software: you can redistribute it and/or modify it
       3             :  * under the terms of the GNU General Public License as published by the
       4             :  * Free Software Foundation, either version 3 of the License, or
       5             :  * (at your option) any later version.
       6             :  *
       7             :  * This file is distributed in the hope that it will be useful, but
       8             :  * WITHOUT ANY WARRANTY; without even the implied warranty of
       9             :  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
      10             :  * See the GNU General Public License for more details.
      11             :  *
      12             :  * You should have received a copy of the GNU General Public License along
      13             :  * with this program.  If not, see <http://www.gnu.org/licenses/>.
      14             :  *
      15             :  * Code by Andrew Tridgell and Siddharth Bharat Purohit
      16             :  */
      17             : 
      18             : #pragma once
      19             : 
      20             : #include "AP_RCProtocol_config.h"
      21             : 
      22             : #if AP_RCPROTOCOL_ST24_ENABLED
      23             : 
      24             : #include "AP_RCProtocol_Backend.h"
      25             : #include "SoftSerial.h"
      26             : 
      27             : #define ST24_DATA_LEN_MAX       64
      28             : #define ST24_MAX_FRAMELEN   70
      29             : #define ST24_STX1               0x55
      30             : #define ST24_STX2               0x55
      31             : 
      32             : /* define range mapping here, -+100% -> 1000..2000 */
      33             : #define ST24_RANGE_MIN 0.0f
      34             : #define ST24_RANGE_MAX 4096.0f
      35             : 
      36             : #define ST24_TARGET_MIN 1000.0f
      37             : #define ST24_TARGET_MAX 2000.0f
      38             : 
      39             : /* pre-calculate the floating point stuff as far as possible at compile time */
      40             : #define ST24_SCALE_FACTOR ((ST24_TARGET_MAX - ST24_TARGET_MIN) / (ST24_RANGE_MAX - ST24_RANGE_MIN))
      41             : #define ST24_SCALE_OFFSET (int)(ST24_TARGET_MIN - (ST24_SCALE_FACTOR * ST24_RANGE_MIN + 0.5f))
      42             : 
      43             : class AP_RCProtocol_ST24 : public AP_RCProtocol_Backend {
      44             : public:
      45        2094 :     AP_RCProtocol_ST24(AP_RCProtocol &_frontend) : AP_RCProtocol_Backend(_frontend) {}
      46             :     void process_pulse(uint32_t width_s0, uint32_t width_s1) override;
      47             :     void process_byte(uint8_t byte, uint32_t baudrate) override;
      48             : private:
      49             :     void _process_byte(uint8_t byte);
      50             :     static uint8_t st24_crc8(uint8_t *ptr, uint8_t len);
      51             :     enum ST24_PACKET_TYPE {
      52             :         ST24_PACKET_TYPE_CHANNELDATA12 = 0,
      53             :         ST24_PACKET_TYPE_CHANNELDATA24,
      54             :         ST24_PACKET_TYPE_TRANSMITTERGPSDATA
      55             :     };
      56             : 
      57             : #pragma pack(push, 1)
      58             :     typedef struct {
      59             :         uint8_t header1;                        ///< 0x55 for a valid packet
      60             :         uint8_t header2;                        ///< 0x55 for a valid packet
      61             :         uint8_t length;                         ///< length includes type, data, and crc = sizeof(type)+sizeof(data[payload_len])+sizeof(crc8)
      62             :         uint8_t type;                           ///< from enum ST24_PACKET_TYPE
      63             :         uint8_t st24_data[ST24_DATA_LEN_MAX];
      64             :         uint8_t crc8;                           ///< crc8 checksum, calculated by st24_common_crc8 and including fields length, type and st24_data
      65             :     } ReceiverFcPacket;
      66             : 
      67             :     /**
      68             :      * RC Channel data (12 channels).
      69             :      *
      70             :      * This is incoming from the ST24
      71             :      */
      72             :     typedef struct {
      73             :         uint16_t t;                     ///< packet counter or clock
      74             :         uint8_t rssi;                   ///< signal strength
      75             :         uint8_t packet_count;           ///< Number of UART packets sent since reception of last RF frame (this tells something about age / rate)
      76             :         uint8_t channel[18];            ///< channel data, 12 channels (12 bit numbers)
      77             :     } ChannelData12;
      78             : 
      79             :     /**
      80             :      * RC Channel data (12 channels).
      81             :      *
      82             :      */
      83             :     typedef struct {
      84             :         uint16_t t;                     ///< packet counter or clock
      85             :         uint8_t rssi;                   ///< signal strength
      86             :         uint8_t packet_count;           ///< Number of UART packets sent since reception of last RF frame (this tells something about age / rate)
      87             :         uint8_t channel[36];            ///< channel data, 24 channels (12 bit numbers)
      88             :     } ChannelData24;
      89             : 
      90             :     /**
      91             :      * Telemetry packet
      92             :      *
      93             :      * This is outgoing to the ST24
      94             :      *
      95             :      * imuStatus:
      96             :      * 8 bit total
      97             :      * bits 0-2 for status
      98             :      * - value 0 is FAILED
      99             :      * - value 1 is INITIALIZING
     100             :      * - value 2 is RUNNING
     101             :      * - values 3 through 7 are reserved
     102             :      * bits 3-7 are status for sensors (0 or 1)
     103             :      * - mpu6050
     104             :      * - accelerometer
     105             :      * - primary gyro x
     106             :      * - primary gyro y
     107             :      * - primary gyro z
     108             :      *
     109             :      * pressCompassStatus
     110             :      * 8 bit total
     111             :      * bits 0-3 for compass status
     112             :      * - value 0 is FAILED
     113             :      * - value 1 is INITIALIZING
     114             :      * - value 2 is RUNNING
     115             :      * - value 3 - 15 are reserved
     116             :      * bits 4-7 for pressure status
     117             :      * - value 0 is FAILED
     118             :      * - value 1 is INITIALIZING
     119             :      * - value 2 is RUNNING
     120             :      * - value 3 - 15 are reserved
     121             :      *
     122             :      */
     123             :     typedef struct {
     124             :         uint16_t t;                     ///< packet counter or clock
     125             :         int32_t lat;                    ///< lattitude (degrees)     +/- 90 deg
     126             :         int32_t lon;                    ///< longitude (degrees)     +/- 180 deg
     127             :         int32_t alt;                    ///< 0.01m resolution, altitude (meters)
     128             :         int16_t vx, vy, vz;             ///< velocity 0.01m res, +/-320.00 North-East- Down
     129             :         uint8_t nsat;                   ///<number of satellites
     130             :         uint8_t voltage;                ///< 25.4V   voltage = 5 + 255*0.1 = 30.5V, min=5V
     131             :         uint8_t current;                ///< 0.5A resolution
     132             :         int16_t roll, pitch, yaw;       ///< 0.01 degree resolution
     133             :         uint8_t motorStatus;            ///< 1 bit per motor for status 1=good, 0= fail
     134             :         uint8_t imuStatus;              ///< inertial measurement unit status
     135             :         uint8_t pressCompassStatus;     ///< baro / compass status
     136             :     } TelemetryData;
     137             : 
     138             : #pragma pack(pop)
     139             : 
     140             :     enum ST24_DECODE_STATE {
     141             :         ST24_DECODE_STATE_UNSYNCED = 0,
     142             :         ST24_DECODE_STATE_GOT_STX1,
     143             :         ST24_DECODE_STATE_GOT_STX2,
     144             :         ST24_DECODE_STATE_GOT_LEN,
     145             :         ST24_DECODE_STATE_GOT_TYPE,
     146             :         ST24_DECODE_STATE_GOT_DATA
     147             :     };
     148             : 
     149             :     enum ST24_DECODE_STATE _decode_state = ST24_DECODE_STATE_UNSYNCED;
     150             :     uint8_t _rxlen;
     151             : 
     152             :     ReceiverFcPacket _rxpacket;
     153             : 
     154             :     SoftSerial ss{115200, SoftSerial::SERIAL_CONFIG_8N1};
     155             : };
     156             : 
     157             : #endif  // AP_RCPROTOCOL_ST24_ENABLED