CAN ID filter problem in <Arduino_CAN.h>

Official Hardware UNO Family UNO R4 WiFi
1

Hello!
I'm trying to write a sketch that tests the CAN hardware filters on the Arduino R4 Wifi, but they don't seem to work. I want to filter messages from a single specific standard ID, but I get all the messages from the network. Does it work for anyone? I'm sharing my sketch:

#include <Arduino_CAN.h>

void setup() {
Serial.begin(115200);
while (!Serial)
;

if (!CAN.begin(CanBitRate::BR_250k)) {
Serial.println("CAN initialization error!");
while (1)
;
}
Serial.println("CAN successfully initialized.");

// Set hardware filters
CAN.setFilterMask_Standard(0x7FF); // standard mask
CAN.setFilterId_Standard(0, 0x123); // mailbox 0

}

void loop() {
if (CAN.available()) {
// Read a frame directly
arduino::CanMsg frame = CAN.read();

Serial.print("Received ID: 0x");
Serial.print(frame.id, HEX);
Serial.print(" LEN: ");
Serial.println(frame.data_length);

for (int i = 0; i < frame.data_length; i++) {
  Serial.print("Data[");
  Serial.print(i);
  Serial.print("] = ");
  Serial.println(frame.data[i], HEX);
}

}
}

Best regards!!

2

Hi @anazkabahn. Have you studied the example sketch that is accessed in Arduino IDE via the File > Examples > Arduino_CAN > CANReadFilter menu item?

I see that it differs from your code in that it iterates over all mailboxes and calls setFilterId_Extended / setFilterId_Standard for each one:

Give that a try and see if you then achieve the expected filtering.

3

Please read the pinned post re 'How to get the most from the forum', paying attention to posting code and errors as well as wiring diagrams.

4

Solved best regards!!!