Sukkin Pang / Mbed 2 deprecated ecu_simulator Featured

CAN-Bus ECU simulator. Only part of the SAE J1979 are implemented. Uses CAN-Bus demo board as hardware platform. http://skpang.co.uk/catalog/canbus-ecu-simulator-with-lpc1768-module-p-1400.html Useful for testing diagnostic tools.

Dependencies:   TextLCD mbed

Fork of ecu_reader by Sukkin Pang

ecu_reader.cpp

Committer:
pangsk
Date:
2012-04-25
Revision:
3:05bb8f0bd7a4
Parent:
0:908be729d27c

File content as of revision 3:05bb8f0bd7a4:

#include "mbed.h"
#include "ecu_reader.h"
#include "globals.h"


// Use a timer to see if things take too long
Timer CANTimer;  
namespace mbed { 


ecu_reader::ecu_reader(int can_speed)
{
    can2.frequency(can_speed);
}


#define TIMEOUT 200
unsigned char ecu_reader::request(unsigned char pid,  char *buffer)
{
    char can_msg[8];
    float engine_data;
        
    led1 = 1;
  
    can_msg[0] = 0x02;  
    can_msg[1] = 0x01;
    can_msg[2] = pid;  
    can_msg[3] = 0;
    can_msg[4] = 0;  
    can_msg[5] = 0;
    can_msg[6] = 0;  
    can_msg[7] = 0;

   if (can2.write(CANMessage(PID_REQUEST, can_msg, 8))) {
         
    }
   
   led1 = 0;
   CANTimer.reset();
   CANTimer.start();
   
   while(CANTimer.read_ms() < TIMEOUT) {
   
   if (can2.read(can_MsgRx)) {
               
        if((can_MsgRx.id == PID_REPLY) && (can_MsgRx.data[2] == pid))
        { 
                        switch(can_MsgRx.data[2])
                        {   /* Details from http://en.wikipedia.org/wiki/OBD-II_PIDs */
                            case ENGINE_RPM:              //   ((A*256)+B)/4    [RPM]
                                engine_data =  ((can_MsgRx.data[3]*256) + can_MsgRx.data[4])/4;
                                sprintf(buffer,"%d rpm ",(int) engine_data);
                                break;
                            
                            case ENGINE_COOLANT_TEMP:     //     A-40              [degree C]
                                engine_data =  can_MsgRx.data[3] - 40;
                                sprintf(buffer,"%d degC ",(int) engine_data);
                            
                            break;
                            
                            case VEHICLE_SPEED:         // A                  [km]
                                engine_data =  can_MsgRx.data[3];
                                sprintf(buffer,"%d km ",(int) engine_data);
                            
                            break;

                            case MAF_SENSOR:               // ((256*A)+B) / 100  [g/s]
                                engine_data =  ((can_MsgRx.data[3]*256) + can_MsgRx.data[4])/100;
                                sprintf(buffer,"%d g/s",(int) engine_data);
                            
                            break;

                            case O2_VOLTAGE:            // A * 0.005   (B-128) * 100/128 (if B==0xFF, sensor is not used in trim calc)
                                engine_data = can_MsgRx.data[3]*0.005;
                                sprintf(buffer,"%d v ",(int) engine_data);
     
                            case THROTTLE:            //
                                engine_data = (can_MsgRx.data[3]*100)/255;
                                sprintf(buffer,"%d %% ",(int) engine_data);
                             
                            
                            break;
                        }
        
                return 1;
        
         }

   }
   }

     return 0;
  



}
} // namespace mbed