Protocol.cpp

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/*
BSD 2-Clause License

Copyright (c) 2019, Simranjeet Singh
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this
   list of conditions and the following disclaimer.

2. Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#include <unistd.h>
#include <eyantra_drone/Protocol.h>
#include <string>

std::string MSP_HEADER="$M<";

int8_t inputBuffer[1024];
uint8_t bufferIndex=0;
//NSMutableArray* requests;


int roll=0;
int pitch=0;
int yaw=0;
float battery=0;
int rssi=0;
float accX=0;
float accY=0;
float accZ=0;
float gyroX=0;
float gyroY=0;
float gyroZ=0;
float magX=0;
float magY=0;
float magZ=0;
float alt=0;

int FC_versionMajor=0;
int FC_versionMinor=0;
int FC_versionPatchLevel=0;

int trim_roll=0;
int trim_pitch=0;

float rcThrottle = 1500, rcRoll = 1500, rcPitch = 1500, rcYaw = 1500, rcAUX1 = 1500, rcAUX2 = 1500, rcAUX3 = 1500, rcAUX4 = 1500;

int Protocol::read8()
{
  return inputBuffer[bufferIndex++] & 0xff;
}

int Protocol::read16()
{
  int add_1=(inputBuffer[bufferIndex++] & 0xff) ;
  int add_2=((inputBuffer[bufferIndex++]) << 8);

  return add_1+add_2;
}

int Protocol::read32()
{
  return (inputBuffer[bufferIndex++] & 0xff) + ((inputBuffer[bufferIndex++] & 0xff) << 8) 
  + ((inputBuffer[bufferIndex++] & 0xff) << 16) + ((inputBuffer[bufferIndex++] & 0xff) << 24);
}

void Protocol::evaluateCommand(int command)
{
  switch (command) {
    
    case MSP_FC_VERSION:
      FC_versionMajor=read8();
      FC_versionMinor=read8();
      FC_versionPatchLevel=read8();

      break;

    case MSP_RAW_IMU:
      
      accX=read16();
      accY=read16();
      accZ=read16();

      gyroX=read16()/8;
      gyroY=read16()/8;
      gyroZ=read16()/8;

      magX=read16()/3;
      magY=read16()/3;
      magZ=read16()/3;

      break;

    case MSP_ATTITUDE:
      //for(int i=0; i<6;i++)
      //NSLog(@"value of %i",inputBuffer[i]);
      roll=(read16()/10);
      pitch=(read16()/10);
      yaw=read16();

      break;

    case MSP_ALTITUDE:
      alt=(read32()/10)-0;
      
      break;

    case MSP_ANALOG:

      battery=(read8()/10.0);
      rssi=read16();

      break;

    case MSP_ACC_TRIM:

      trim_pitch=read16();
      trim_roll=read16();

      break;

    case MSP_RC:

      rcRoll = read16();
      rcPitch = read16();
      rcYaw = read16();
      rcThrottle = read16();
      rcAUX1 = read16();
      rcAUX2 = read16();
      rcAUX3 = read16();
      rcAUX4 = read16();

      break;
    
    default:
      break;
  }
}

void Protocol::sendRequestMSP(std::vector<int8_t> data)
{
  com.writeSock(&data[0],data.size());
}

void Protocol::sendMulRequestMSP(std::vector<int8_t> data, int i)
{
  com.writeMulSock(&data[0],data.size(),i);
}

std::vector<int8_t>  Protocol::createPacketMSP(int msp, std::vector<int8_t>payload)
{
  if (msp < 0) {
    //return NULL;
  }
  std::vector<int8_t> bf;
  for(std::string::iterator it = MSP_HEADER.begin(); it != MSP_HEADER.end(); ++it) {
    bf.push_back((int8_t) (*it & 0xFF));
  }
  int8_t checksum = 0;
  int8_t pl_size = (int8_t) ((!payload.empty() ? (int) (payload.size()) : 0) & 0xFF);
  bf.push_back(pl_size);
  checksum ^= (pl_size & 0xFF);

  bf.push_back((int8_t) (msp & 0xFF));
  checksum ^= (msp & 0xFF);

  if (!payload.empty()) {
    //printf("Adding payload %d\n");
    for (std::vector<int8_t>::iterator it = payload.begin() ; it != payload.end(); ++it) {
      int8_t k=*it;
      //printf("payload  value %i\n",k);
      bf.push_back((int8_t) (k & 0xFF));
      checksum ^= (k & 0xFF);
    }
  }
  bf.push_back(checksum);
  return (bf);
}

void Protocol::sendRequestMSP_SET_RAW_RC(int channels[])
{
  std::vector<int8_t>rc_signals(16);
  int index = 0;
  for (int i = 0; i < 8; i++) {
    //Log.d("drona", "Data: " + (channels8[i]));
    rc_signals[index++] = (int8_t) (channels[i] & 0xFF);
    rc_signals[index++] = (int8_t) ((channels[i] >> 8) & 0xFF);
    //printf("rcvalue = %i\n" ,channels[i]);
    //rc_signals.push_back((uint8_t) (channels[i] & 0xFF));
    //rc_signals.push_back( (uint8_t) ((channels[i] >> 8) & 0xFF));
  }
  //printf("size of rc_array %d\n",rc_signals.size() );
  sendRequestMSP(createPacketMSP(MSP_SET_RAW_RC, rc_signals));
}

void Protocol::sendMulRequestMSP_SET_RAW_RC(int channels[])
{
  std::vector<int8_t>rc_signals(16);
  int index = 0;
  int droneNumber = channels[8];
  for (int i = 0; i < 8; i++) {
    //Log.d("drona", "Data: " + (channels8[i]));
    rc_signals[index++] = (int8_t) (channels[i] & 0xFF);
    rc_signals[index++] = (int8_t) ((channels[i] >> 8) & 0xFF);
    //printf("rcvalue = %i\n" ,channels[i]);
    //rc_signals.push_back((uint8_t) (channels[i] & 0xFF));
    //rc_signals.push_back( (uint8_t) ((channels[i] >> 8) & 0xFF));
  }
  //printf("size of rc_array %d\n",rc_signals.size() );
  sendMulRequestMSP(createPacketMSP(MSP_SET_RAW_RC, rc_signals), droneNumber);
}

void Protocol::sendRequestMSP_SET_POS(int posArray[])
{
  std::vector<int8_t>posData(8);
  int index = 0;
  for (int i = 0; i < 4; i++) {
    //Log.d("drona", "Data: " + (channels8[i]));
    posData[index++] = (int8_t) (posArray[i] & 0xFF);
    posData[index++] = (int8_t) ((posArray[i] >> 8) & 0xFF);

    //  printf("posvalue = %i\n" ,posArray[i]);
    // rc_signals.push_back((uint8_t) (channels[i] & 0xFF));
    //rc_signals.push_back( (uint8_t) ((channels[i] >> 8) & 0xFF));
  }
  sendRequestMSP(createPacketMSP(MSP_SET_POS, posData));
}

void Protocol::sendRequestMSP_GET_DEBUG(std::vector<int> requests)
{
  for (size_t i = 0; i < requests.size(); i++) {
    
      sendRequestMSP(createPacketMSP(requests[i], std::vector<int8_t>()));
    
  }
}

void Protocol::sendMulRequestMSP_GET_DEBUG(std::vector<int> requests, int index)
{
  for (size_t i = 0; i < requests.size(); i++) {
    
      sendMulRequestMSP(createPacketMSP(requests[i], std::vector<int8_t>()), index);
    
  }
}