50.7.2.3 Transmit Mailbox
When transmitting a message, the message length and data are written to the transmit mailbox with the correct identifier. For each transmit mailbox, a priority is assigned. The controller automatically sends the message with the highest priority first (set in the CAN_MMRx.PRIOR field).
It is also possible to configure a mailbox in Producer mode. In this mode, when a remote frame is received, the mailbox data are sent automatically. By enabling this mode, a producer can be done using only one mailbox instead of two: one to detect the remote frame and one to send the answer.
| Object Type | Description |
|---|---|
| Transmit | The message stored in the
mailbox data registers will try to win the bus arbitration immediately or later
according to the Time Management Unit configuration (see Time Management
Unit). The application is notified that the message has been sent or aborted. |
| Producer | The message prepared in the mailbox data registers will be sent after receiving the next remote frame. This extends transmit mailbox features. |