bmw_sbox.cpp

/*   * This file is part of the ZombieVerter project.
 *
 * Copyright (C) 2010 Johannes Huebner <contact@johanneshuebner.com>
 * Copyright (C) 2010 Edward Cheeseman <cheesemanedward@gmail.com>
 * Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
 * Copyright (C) 2019-2022 Damien Maguire <info@evbmw.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <bmw_sbox.h>

/*
 * Implements control of the contactors in the BMW PHEV battery box "SBOX" unit.
 * Reads batter parameters from SBOX.
 * See : https://github.com/damienmaguire/BMW_SBox
 */

int32_t SBOX::Amperes;
int32_t SBOX::Ah;
int32_t SBOX::KW;
int32_t SBOX::KWh;
int32_t SBOX::Voltage=0;
int32_t SBOX::Voltage2=0;
int32_t SBOX::Temperature;
uint8_t canCtr100=0;
uint8_t CCByte=0;
uint8_t CRCByte=0;
uint8_t Timer20ms=0;


//BMW(Maxim crc poly 0x31) CRC 8 lookup table
uint8_t crc_array[256] =
{
    0x00, 0x5e, 0xbc, 0xe2, 0x61, 0x3f, 0xdd, 0x83,
    0xc2, 0x9c, 0x7e, 0x20, 0xa3, 0xfd, 0x1f, 0x41,
    0x9d, 0xc3, 0x21, 0x7f, 0xfc, 0xa2, 0x40, 0x1e,
    0x5f, 0x01, 0xe3, 0xbd, 0x3e, 0x60, 0x82, 0xdc,
    0x23, 0x7d, 0x9f, 0xc1, 0x42, 0x1c, 0xfe, 0xa0,
    0xe1, 0xbf, 0x5d, 0x03, 0x80, 0xde, 0x3c, 0x62,
    0xbe, 0xe0, 0x02, 0x5c, 0xdf, 0x81, 0x63, 0x3d,
    0x7c, 0x22, 0xc0, 0x9e, 0x1d, 0x43, 0xa1, 0xff,
    0x46, 0x18, 0xfa, 0xa4, 0x27, 0x79, 0x9b, 0xc5,
    0x84, 0xda, 0x38, 0x66, 0xe5, 0xbb, 0x59, 0x07,
    0xdb, 0x85, 0x67, 0x39, 0xba, 0xe4, 0x06, 0x58,
    0x19, 0x47, 0xa5, 0xfb, 0x78, 0x26, 0xc4, 0x9a,
    0x65, 0x3b, 0xd9, 0x87, 0x04, 0x5a, 0xb8, 0xe6,
    0xa7, 0xf9, 0x1b, 0x45, 0xc6, 0x98, 0x7a, 0x24,
    0xf8, 0xa6, 0x44, 0x1a, 0x99, 0xc7, 0x25, 0x7b,
    0x3a, 0x64, 0x86, 0xd8, 0x5b, 0x05, 0xe7, 0xb9,
    0x8c, 0xd2, 0x30, 0x6e, 0xed, 0xb3, 0x51, 0x0f,
    0x4e, 0x10, 0xf2, 0xac, 0x2f, 0x71, 0x93, 0xcd,
    0x11, 0x4f, 0xad, 0xf3, 0x70, 0x2e, 0xcc, 0x92,
    0xd3, 0x8d, 0x6f, 0x31, 0xb2, 0xec, 0x0e, 0x50,
    0xaf, 0xf1, 0x13, 0x4d, 0xce, 0x90, 0x72, 0x2c,
    0x6d, 0x33, 0xd1, 0x8f, 0x0c, 0x52, 0xb0, 0xee,
    0x32, 0x6c, 0x8e, 0xd0, 0x53, 0x0d, 0xef, 0xb1,
    0xf0, 0xae, 0x4c, 0x12, 0x91, 0xcf, 0x2d, 0x73,
    0xca, 0x94, 0x76, 0x28, 0xab, 0xf5, 0x17, 0x49,
    0x08, 0x56, 0xb4, 0xea, 0x69, 0x37, 0xd5, 0x8b,
    0x57, 0x09, 0xeb, 0xb5, 0x36, 0x68, 0x8a, 0xd4,
    0x95, 0xcb, 0x29, 0x77, 0xf4, 0xaa, 0x48, 0x16,
    0xe9, 0xb7, 0x55, 0x0b, 0x88, 0xd6, 0x34, 0x6a,
    0x2b, 0x75, 0x97, 0xc9, 0x4a, 0x14, 0xf6, 0xa8,
    0x74, 0x2a, 0xc8, 0x96, 0x15, 0x4b, 0xa9, 0xf7,
    0xb6, 0xe8, 0x0a, 0x54, 0xd7, 0x89, 0x6b, 0x35,
};

uint8_t BMW_crc8(const uint8_t * data, const uint16_t size)
{
    uint8_t crc = 0;
    for ( uint16_t i = 0; i < size; ++i )
    {
         crc = crc_array[data[i] ^ crc];
    }
    return crc;
}

void SBOX::RegisterCanMessages(CanHardware* can)
{
   can->RegisterUserMessage(0x200);//SBOX MSG
   can->RegisterUserMessage(0x210);//SBOX MSG
   can->RegisterUserMessage(0x220);//SBOX MSG

}

void SBOX::DecodeCAN(int id, uint32_t data[2])
{
   switch (id)
   {
   case 0x200:
      SBOX::handle200(data);//SBOX CAN MESSAGE
      break;
   case 0x210:
      SBOX::handle210(data);//SBOX CAN MESSAGE
      break;
   case 0x220:
      SBOX::handle220(data);//SBOX CAN MESSAGE
      break;
   }
}


void SBOX::handle200(uint32_t data[2])  //SBOX Current

{
   uint8_t* bytes = (uint8_t*)data;// arrgghhh this converts the two 32bit array into bytes. See comments are useful:)
   Amperes = ((bytes[2] << 16) | (bytes[1] << 8) | (bytes[0]));
   Amperes = (Amperes<<8) >> 8;//extend sign bit as its a 24 bit signed value in a 32bit int! AAAHHHHHH!

}

void SBOX::handle210(uint32_t data[2])  //SBOX battery voltage

{
   uint8_t* bytes = (uint8_t*)data;// arrgghhh this converts the two 32bit array into bytes. See comments are useful:)
   Voltage=((bytes[2] << 16) | (bytes[1] << 8) | (bytes[0]));
   Voltage = (Voltage<<8) >> 8;//extend sign bit as its a 24 bit signed value in a 32bit int! AAAHHHHHH!
}

void SBOX::handle220(uint32_t data[2]) //SBOX Output voltage

{
   uint8_t* bytes = (uint8_t*)data;// arrgghhh this converts the two 32bit array into bytes. See comments are useful:)
   Voltage2=((bytes[2] << 16) | (bytes[1] << 8) | (bytes[0]));
   Voltage2 = (Voltage2<<8) >> 8;//extend sign bit as its a 24 bit signed value in a 32bit int! AAAHHHHHH!

}

void SBOX::ControlContactors(int opmode, CanHardware* can)
{
   uint8_t bytes[8];
   bytes[0]=0xFF;//sems to control the iso relay
   bytes[1]=0xFE;//needs to be 0xFE to enable contactors.
   bytes[2]=0xFF;
   bytes[3]=0xFF;
   can->Send(0x300, (uint32_t*)bytes,4);

   bytes[0]=CCByte;
   bytes[1]=(canCtr100<<4|0x1);
   bytes[2]=0xFF;
   bytes[3]=0x00;//crc
   bytes[4]=0x00;
   bytes[5]=0x00;
   bytes[6]=0x00;
   bytes[7]=0x00;


   canCtr100++;
   if(canCtr100>0xE) canCtr100=0;

      switch (opmode)
   {
      case 0:
        CCByte=0x00;//all contactors off
         break;
      case 2://Precharge
        CCByte=0xA6;//Prech and Neg contactors activated
         break;

      case 1://Run
        CCByte=0xAA;//All contactors activated
         break;

      case 4://Charge
        CCByte=0xAA;//All contactors activated
         break;

      case 3://Precharge fail
        CCByte=0x00;//all contactors off
         break;

    }
   CRCByte = BMW_crc8(bytes,8);
   bytes[3]=CRCByte;//crc
   can->Send(0x100, (uint32_t*)bytes,4);

}