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api / mbed / trunk / CAN

CANMessage

class CANMessage : public CAN_Message

CANMessage
Functions
CANMessage	Creates empty CAN message.
CANMessage	Creates CAN message with specific content.
CANMessage	Creates CAN remote message.
Variables
id	The message id.
data	Space for 8 byte payload.
len	Length of data in bytes.
format	Defines if the message has standard or extended format.
type	Defines the type of a message.
CAN	A can bus client, used for communicating with can devices
Functions
CAN	Creates an CAN interface connected to specific pins.
frequency	Set the frequency of the CAN interface
write	Write a CANMessage to the bus.
read	Read a CANMessage from the bus.
reset	Reset CAN interface.
monitor	Puts or removes the CAN interface into silent monitoring mode
rderror	Returns number of read errors to detect read overflow errors.
tderror	Returns number of write errors to detect write overflow errors.
attach	Attach a function to call whenever a CAN frame received interrupt is generated.

Functions

CANMessage

CANMessage()

Creates empty CAN message.

CANMessage

CANMessage( int _id,
const char * _data,
char _len = 8,
CANType _type = CANData,
CANFormat _format = CANStandard )

Creates CAN message with specific content.

CANMessage

CANMessage( int _id,
CANFormat _format = CANStandard )

Creates CAN remote message.

Variables

id

unsigned int id

The message id.

If format is CANStandard it must be an 11 bit long id If format is CANExtended it must be an 29 bit long id

data

unsigned char data[8]

Space for 8 byte payload.

If type is CANData data can store up to 8 byte data.

len

unsigned char len

Length of data in bytes.

If type is CANData data can store up to 8 byte data.

format

CANFormat format

Defines if the message has standard or extended format.

Defines the type of message id

Default is CANStandard which implies 11 bit id. CANExtended means 29 bit message id.

type

CANType type

Defines the type of a message.

The message type can rather be CANData for a message with data (default). Or CANRemote for a request of a specific CAN message.

CAN

class CAN : public Base

A can bus client, used for communicating with can devices

Functions
CAN	Creates an CAN interface connected to specific pins.
frequency	Set the frequency of the CAN interface
write	Write a CANMessage to the bus.
read	Read a CANMessage from the bus.
reset	Reset CAN interface.
monitor	Puts or removes the CAN interface into silent monitoring mode
rderror	Returns number of read errors to detect read overflow errors.
tderror	Returns number of write errors to detect write overflow errors.
attach	Attach a function to call whenever a CAN frame received interrupt is generated.

Functions

CAN

CAN( PinName rd,
PinName td )

Creates an CAN interface connected to specific pins.

Example

#include "mbed.h"

Ticker ticker;
DigitalOut led1(LED1);
DigitalOut led2(LED2);
CAN can1(p9, p10);
CAN can2(p30, p29);

char counter = 0;

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

int main() {
    ticker.attach(&send, 1);
   CANMessage msg;
    while(1) {
        if(can2.read(msg)) {
            printf("Message received: %d\n\n", msg.data[0]);
            led2 = !led2;
        }
        wait(0.2);
    }
}

Variables

rd	read from transmitter
td	transmit to transmitter

frequency

int frequency( int hz )

Set the frequency of the CAN interface

Variables

hz	The bus frequency in hertz
returns	1 if successful, 0 otherwise

write

int write( CANMessage msg )

Write a CANMessage to the bus.

Variables

msg	The CANMessage to write.

Returns

0	If write failed.
1	If write was successful.

read

int read( CANMessage & msg )

Read a CANMessage from the bus.

Variables

msg	A CANMessage to read to.

Returns

0	If no message arrived.
1	If message arrived.

reset

void reset()

Reset CAN interface.

To use after error overflow.

monitor

void monitor( bool silent )

Puts or removes the CAN interface into silent monitoring mode

Variables

silent

boolean indicating whether to go into silent mode or not

rderror

unsigned char rderror()

Returns number of read errors to detect read overflow errors.

tderror

unsigned char tderror()

Returns number of write errors to detect write overflow errors.

attach

void attach( void (*fptr)(void) )

Attach a function to call whenever a CAN frame received interrupt is generated.

Variables

fptr	A pointer to a void function, or 0 to set as none

class CANMessage : public CAN_Message

CANMessage()

Creates empty CAN message.

unsigned int id

The message id.

unsigned char data[8]

Space for 8 byte payload.

unsigned char len

Length of data in bytes.

CANFormat format

Defines if the message has standard or extended format.

CANType type

Defines the type of a message.

class CAN : public Base

A can bus client, used for communicating with can devices

CAN( PinName rd,
PinName td )

Creates an CAN interface connected to specific pins.

int frequency( int hz )

Set the frequency of the CAN interface

int write( CANMessage msg )

Write a CANMessage to the bus.

int read( CANMessage & msg )

Read a CANMessage from the bus.

void reset()

Reset CAN interface.

void monitor( bool silent )

Puts or removes the CAN interface into silent monitoring mode

unsigned char rderror()

Returns number of read errors to detect read overflow errors.

unsigned char tderror()

Returns number of write errors to detect write overflow errors.

void attach( void (*fptr)(void) )

Attach a function to call whenever a CAN frame received interrupt is generated.