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CAN class hierarchy

Controller-Area Network (CAN) is a bus standard that allows microcontrollers and devices to communicate with each other without going through a host computer.

Note: You can use the CAN interface to write data words out of a CAN port. It will return the data received from another CAN device. You can configure the CAN clock frequency.

CAN class reference

Public Types
enum  Mode {
  Reset = 0, Normal, Silent, LocalTest,
  GlobalTest, SilentTest
enum  IrqType {
  RxIrq = 0, TxIrq, EwIrq, DoIrq,
  WuIrq, EpIrq, AlIrq, BeIrq,
  IdIrq, IrqCnt
Public Member Functions
 CAN (PinName rd, PinName td)
 CAN (PinName rd, PinName td, int hz)
int frequency (int hz)
int write (CANMessage msg)
int read (CANMessage &msg, int handle=0)
void reset ()
void monitor (bool silent)
int mode (Mode mode)
int filter (unsigned int id, unsigned int mask, CANFormat format=CANAny, int handle=0)
unsigned char rderror ()
unsigned char tderror ()
void attach (Callback< void()> func, IrqType type=RxIrq)
template<typename T >
void attach (T *obj, void(T::*method)(), IrqType type=RxIrq)
template<typename T >
void attach (T *obj, void(*method)(T *), IrqType type=RxIrq)
Static Public Member Functions
static void _irq_handler (uint32_t id, CanIrqType type)
Protected Member Functions
virtual void lock ()
virtual void unlock ()
Protected Attributes
can_t _can
Callback< void()> _irq [IrqCnt]
PlatformMutex _mutex

CAN Hello World!

This example sends a counter from one CAN bus (can1) and listens for a packet on the other CAN bus (can2). Each bus controller should be connected to a CAN bus transceiver. These should be connected together at a CAN bus.

#include "mbed.h"

Ticker ticker;
DigitalOut led1(LED1);
DigitalOut led2(LED2);
char counter = 0;

void send() {
    if(can1.write(CANMessage(1337, &counter, 1))) {
        printf("Message sent: %d\n", counter);
    led1 = !led1;

int main() {
    ticker.attach(&send, 1);
    CANMessage msg;
    while(1) {
        if(can2.read(msg)) {
            printf("Message received: %d\n", msg.data[0]);
            led2 = !led2;

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