Clear CANbus buffer

Using Arduino Programming Questions
1

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)
https://www.arduinolibraries.info/libraries/can-bus-shield

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..

Thanks.

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()
{
    Serial.begin(115200);

    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");
        delay(100);
    }
    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.println("-----------------------------");
        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);
            Serial.print("\t");
        }
        Serial.println();
    }
}
2

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4

Added code to first post

5

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