Clear CANbus buffer

Hi All,

I am using the Arduino Mega 2560 in combination with the Seeedstudio CAN-BUS Shield V2.0.
Library v1.0.0 (older version)

I am trying to create a test device which I connect to a CAN module and request some data.
When the tested CAN module is decoupled and a new one is attached which is defective or not connected at all, then the old CAN messages are still present when reading the CAN message with
CAN.readMsgBufID(&id, &RecMessageLen, RecMessage.U8);

Is there a way to clean the buffer?
Or should I set them all to Zero before reading the MsgBufID?

Is anyone with the change to library v2.3.0, would it improve this part as well?
Edit: tried the new library version, normal operations, that version is working with the Raspberry version as well..


This is for now done with the default demo "receive_check":

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

// the cs pin of the version after v1.1 is default to D9
// v0.9b and v1.0 is default D10
const int SPI_CS_PIN = 9;

MCP_CAN CAN(SPI_CS_PIN);                                    // Set CS pin

void setup()

    while (CAN_OK != CAN.begin(CAN_500KBPS))              // init can bus : baudrate = 500k
        Serial.println("CAN BUS Shield init fail");
        Serial.println(" Init CAN BUS Shield again");
    Serial.println("CAN BUS Shield init ok!");

void loop()
    unsigned char len = 0;
    unsigned char buf[8];

    if(CAN_MSGAVAIL == CAN.checkReceive())            // check if data coming
        CAN.readMsgBuf(&len, buf);    // read data,  len: data length, buf: data buf

        unsigned long canId = CAN.getCanId();
        Serial.print("Get data from ID: 0x");
        Serial.println(canId, HEX);

        for(int i = 0; i<len; i++)    // print the data
            Serial.print(buf[i], HEX);

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