For this combination the Tx buffers section in the Message RAM is separated in two parts:
- Dedicated Tx buffers: the number of Dedicated Tx
buffers is configured by the MCAN_TXBC.NDTB field
- Tx FIFO: the number of Tx buffers assigned to the
Tx FIFO is configured by the MCAN_TXBC.TFQS field
If the MCAN_TXBC.TFQS field is empty (zero) - only
Dedicated Tx buffers are used.
Tx prioritization:
- Scan Dedicated Tx buffers and oldest pending Tx
FIFO Buffer (referenced by the MCAN_TXFQS.TFGI field)
- Buffer with lowest Message ID gets highest priority and is transmitted next
Figure 34-17 shows Mixed Dedicated Tx buffers/Tx FIFO example.