Dual_CAN_filter_block.ino

// Based on example written by: Cory J. Fowler

#include <mcp_can.h>
#include <SPI.h>

unsigned long rxId;
unsigned long rxIdToBlock = 0x128; // in my case it is the same for every rxBlock
byte len;
byte rxBuf[8];

byte txBuf0[] = {0xAA,0x55,0xAA,0x55,0xAA,0x55,0xAA,0x55};
byte txBuf1[] = {0x55,0xAA,0x55,0xAA,0x55,0xAA,0x55,0xAA};
char msgString[128];                        // Array to store serial string

MCP_CAN CAN0(9);                              // IN CAN0 interface usins CS on digital pin 9
MCP_CAN CAN1(10);                               // OUT CAN1 interface using CS on digital pin 10

#define CAN0_INT 3    //define interrupt pin for CAN0 recieve buffer
#define CAN1_INT 4    //define interrupt pin for CAN1 recieve buffer

// rxBuffers to block
const byte rxBlock1[] = {0xC2, 0xB0, 0x01, 0x02, 0x00, 0xC0, 0x04, 0x00};
const byte rxBlock2[] = {0xC4, 0xB0, 0x01, 0x02, 0x00, 0xC0, 0x04, 0x00};
const byte rxBlock3[] = {0xC6, 0xB0, 0x01, 0x02, 0x00, 0xC0, 0x06, 0x00};
const byte rxBlock4[] = {0xC0, 0xB0, 0x01, 0x02, 0x00, 0xC0, 0x06, 0x00};

void setup()
{
  Serial.begin(115200);
  
  pinMode(CAN0_INT, INPUT_PULLUP);
  pinMode(CAN1_INT, INPUT_PULLUP);
  
  // init CAN0 bus, baudrate: 250k@16MHz
  if(CAN0.begin(MCP_ANY, CAN_250KBPS, MCP_16MHZ) == CAN_OK){
  Serial.print("CAN0: Init OK!\r\n");
  CAN0.setMode(MCP_NORMAL);
  } else Serial.print("CAN0: Init Fail!!!\r\n");
  
  // init CAN1 bus, baudrate: 250k@16MHz
  if(CAN1.begin(MCP_ANY, CAN_250KBPS, MCP_16MHZ) == CAN_OK){
  Serial.print("CAN1: Init OK!\r\n");
  CAN1.setMode(MCP_NORMAL);
  } else Serial.print("CAN1: Init Fail!!!\r\n");
  
  SPI.setClockDivider(SPI_CLOCK_DIV2);         // Set SPI to run at 8MHz (16MHz / 2 = 8 MHz)
  
  CAN0.sendMsgBuf(0x1000000, 1, 8, txBuf0);
  CAN1.sendMsgBuf(0x1000001, 1, 8, txBuf1);
}

void loop(){  
    
  CAN0.readMsgBuf(&rxId, &len, rxBuf);       // Read data: len = data length, buf = data byte(s)

  int block1 = memcmp(rxBlock1, rxBuf, len);
  int block2 = memcmp(rxBlock2, rxBuf, len);
  int block3 = memcmp(rxBlock3, rxBuf, len);
  int block4 = memcmp(rxBlock4, rxBuf, len);

  if (rxId != rxIdToBlock 
      && len != sizeof (rxBlock1 || rxBlock2 || rxBlock3 || rxBlock4)
      && 0 != (block1 || block2 || block3 || block4)) {
        CAN1.sendMsgBuf(rxId, 1, len, rxBuf); // Immediately send message out CAN1 interface
  }     
  
  if((rxId & 0x80000000) == 0x80000000)      // Determine if ID is standard (11 bits) or extended (29 bits)
    sprintf(msgString, "Extended ID: 0x%.8lX  DLC: %1d  Data:", (rxId & 0x1FFFFFFF), len);
  else
    sprintf(msgString, "Standard ID: 0x%.3lX       DLC: %1d  Data rxId:", rxId, len);

  Serial.print(msgString);

  if((rxId & 0x40000000) == 0x40000000){    // Determine if message is a remote request frame.
    sprintf(msgString, " REMOTE REQUEST FRAME");
    Serial.print(msgString);
  } else {
    for(byte i = 0; i<len; i++){
      sprintf(msgString, " 0x%.2X", rxBuf[i]);
      Serial.print(msgString);
    }
  }
      
  Serial.println();
  
}