CAN_tx_object

#include <rtx_can.h>

CAN_ERROR CAN_tx_object (
    U32 ctrl,              /* CAN Controller */
    U32 channel,           /* CAN Channel Number */
    U32 id,                /* Message ID */
    U32 object_para);      /* Object Parameters */

The CAN_tx_object function enables message transmission for the CAN controller specified by ctrl on the specified channel. Once enabled, the CAN controller can transmit messages matching the specified id. The object_para may be one of the following:

• DATA_TYPE
  DATA FRAME message type.
• REMOTE_TYPE
  REMOTE FRAME message type.
• STANDARD_TYPE
  Message with standard 11-bit identifier type.
• EXTENDED_TYPE
  Message with extended 29-bit identifier type.

Note

Types DATA_TYPE or REMOTE_TYPE can be used together with STANDARD_TYPE or EXTENDED_TYPE (type specifiers can be bit-ored together).

The CAN_tx_object function is part of RL-CAN. The prototype is defined in RTX_CAN.h.

Note

• Enabling a transmission object is not necessary for many microcontrollers (like the NXP LPC2000 and ST Microelectronics STR7 devices) because they can send CAN messages without configuring a transmission object. As such, this function is not implemented for some devices.
• For devices like the ST Microelectronics STR7, you must leave at least one message object available for message transmission. You cannot initialize the object as a receive object and use it for transmission.
• Some CAN controllers, like that used in the NXP LPC2000 devices, do not use the channel information. For these devices, you should specify a value of 0 for the channel.

The CAN_tx_object function returns one of the following manifest constants.

• CAN_OK
  Success.
• CAN_OBJECTS_FULL_ERROR
  Indicates that no more transmit or receive objects may be defined.

CAN_rx_object

#include <rtx_can.h>

void main (void) {
  CAN_tx_object (1, 2, 33, DATA_TYPE | STANDARD_TYPE);

  // Enable DATA message transmission on controller 1,
  // channel 2, with STANDARD 11-bit ID 33
}