DJIRemote2.h

Go to the documentation of this file.

#ifndef VTM_RECEIVER_H
#define VTM_RECEIVER_H
 
#include "mbed.h"
#include <cstdint>
#include <cstddef>
 
struct VTMInput {
    uint16_t ch0 = 1024;
    uint16_t ch1 = 1024;
    uint16_t ch2 = 1024;
    uint16_t ch3 = 1024;
 
    uint8_t mode = 1;
    uint8_t pause = 0;
    uint8_t btnL = 0;
    uint8_t btnR = 0;
 
    uint16_t dial = 1024;
    uint8_t trigger = 0;
 
    int16_t mouseX = 0;
    int16_t mouseY = 0;
    int16_t mouseZ = 0;
 
    uint8_t mouseL = 0;
    uint8_t mouseR = 0;
    uint8_t mouseM = 0;
 
    uint16_t keyboard = 0;
    uint16_t CRC_in = 0;
};
 
class DJIRemote2 {
public:
    static constexpr uint8_t HEADER_BYTE_0 = 0xA9;
    static constexpr uint8_t HEADER_BYTE_1 = 0x53;
    static constexpr size_t FRAME_SIZE = 21;
    static constexpr size_t STREAM_BUFFER_SIZE = 64;
    static constexpr float STICK_MAX_VALUE = 1684.0f;
 
    DJIRemote2(PinName tx, PinName rx, int baud = 921600);
 
    bool update();                      // returns true when a full new frame is decoded
    void clear();
    void zeroInputs();  
 
    uint64_t prevFrameTime = 0;         
 
    const VTMInput& getData() const;
    bool hasValidFrame() const;
 
    uint64_t getLastFrameTimeUs() const;
    uint64_t getFramePeriodUs() const;
    double getFrameRateHz() const;
 
    // specifies a particular joystick
    enum class Joystick
    {
        RIGHT_HORIZONTAL,
        RIGHT_VERTICAL,
        LEFT_HORIZONTAL,
        LEFT_VERTICAL
    };
 
    // specifies a particular mode 
    enum class ModeSwitch
    {
        MODE_C,
        MODE_N,
        MODE_S
    };
 
    // A list of the particular keys to interact with, in bit order.
    enum class Key
    {
        W = 0,
        S,
        A,
        D,
        SHIFT,
        CTRL,
        Q,
        E,
        R,
        F,
        G,
        Z,
        X,
        C,
        V,
        B
    };
 
    // check if trigger is pressed
    bool TriggerPressed() const;
    // check if custom left button is pressed
    bool CUSTLPressed() const;
    // check if custom right button is pressed
    bool CUSTRPressed() const;
    // check if pause button is pressed
    bool PAUSEPressed() const;
    
    int16_t getMouseX() const;
 
    int16_t getMouseY() const;
 
    int16_t getMouseZ() const;
 
    bool getMouseL() const;
 
    bool getMouseR() const;
 
    bool keyPressed(Key key) const;
 
    int16_t getWheel() const;
 
    bool CUSTLToggled() const;
    bool CUSTRToggled() const;
    bool PAUSEToggled() const;
 
    float getJoystickValue(Joystick joy) const;
    float apply_deadzone(float value) const;
    float getDialValue() const;
    ModeSwitch getMode() const;
 
private:
    BufferedSerial serial_;
 
    uint8_t streamBuffer_[STREAM_BUFFER_SIZE];
    size_t streamCount_;
 
    VTMInput data_;
    bool validFrame_;
 
    uint64_t lastFrameTimeUs_;
    uint64_t currentFrameTimeUs_;
    uint64_t framePeriodUs_;
 
 
    void readIncomingBytes();
    bool tryParseFrame();
    int findHeader() const;
    void decodeFrame(const uint8_t* frame);
    void shiftLeft(size_t count);
};
 
#endif