Spektrum.h

/*
  Spektrum.h
  Spektrum serial receiver mbed library
  Dennis Evangelista, 2018
*/

#ifndef SPEKTRUM_H
#define SPEKTRUM_H
#define SPEKTRUM_VERSION "1.0.1"

#include "mbed.h"
#include "rtos.h"

// bind modes
#define SPEKTRUM_INT_DSMX_22MS 7
#define SPEKTRUM_EXT_DSMX_22MS 8
#define SPEKTRUM_INT_DSMX_11MS 9
#define SPEKTRUM_EXT_DSMX_11MS 10
// DSM2 bind modes not recommended, not implemented
// EXT(ernal) bind modes don't really work on solitary satellite receiver

// field definitions
// #define SPEKTRUM_MASK_1024_CHANID 0xfc00
// #define SPEKTRUM_MASK_1024_SXPOS 0x03ff
// first two only used in DSM2 which are not implemented
#define SPEKTRUM_MASK_2048_CHANID 0x7800
#define SPEKTRUM_MASK_2048_CHANID_MSB 0x78
#define SPEKTRUM_MASK_2048_SXPOS 0x07ff

// allowable system field values
// #define SPEKTRUM_22MS_1024_DSM2 0x01
// #define SPEKTRUM_11MS_2048_DSM2 0x12
#define SPEKTRUM_22MS_2048_DSMX 0xa2
#define SPEKTRUM_11MS_2048_DSMX 0xb2

#define SPEKTRUM_BAUD 115200
// Spektrum baud is supposed to be 125000, but the LPC1768 seems not
// to support nonstandard baud rates.

#define SPEKTRUM_SERVOS 7
#define SPEKTRUM_PACKET_SIZE 16
#define SPEKTRUM_CHANNELS 16
#define SPEKTRUM_COUNT2US(x) (x*600/1024+900)




/** Spektrum receiver object for connecting to eg SPM9745 receiver
 */
class Spektrum{
 public:
  /** Number of fades (failed packets) from receiver */
  unsigned int fades;
  
  /** Tells if system is in DSMX 11ms or 22ms for example */
  unsigned int system; 

  /** Contains 0-2048 values for all channels 0-15 */ 
  unsigned int channel[SPEKTRUM_CHANNELS];

  /** Contains approx 900-2100us pulsewidths corresponding to chan 0-15 */
  unsigned int pulsewidth[SPEKTRUM_CHANNELS];

  /** If true, data is value */ 
  bool valid;  // TODO switch to EventFlags?

  /** 11 or 22 ms */ 
  unsigned int period_ms;
  
  Spektrum(PinName tx, PinName rx); // constructor
  ~Spektrum(); // destructor

 private:
  UARTSerial _rx;
  unsigned char _buf[SPEKTRUM_PACKET_SIZE]; 
  Thread _packet_thread;
  void _packet_callback(void); 
};







/** For binding a Spektrum receiver to transmitter */ 
class BindPlug{
 public:
  /** e.g. SPEKTRUM_INT_DSMX_11MS, SPEKTRUM_INT_DSMX_22MS */
  int mode;
  
  BindPlug(PinName tx, PinName rx, int mode = SPEKTRUM_INT_DSMX_11MS);
  ~BindPlug();
  void bind();

 private:
  DigitalOut _3Vpin;
  DigitalOut _datapin;
};

/* LATER
class SpektrumTestDevice{
 public:
  unsigned int fades;
  unsigned int servo[7];
  SpektrumTestDevice(PinName tx, PinName rx);
  ~SpektrumTestDevice();

 private:
  Serial _receiver; 
};
*/

#endif