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[21-16] NDTB field
- Tx FIFO: the number of Tx Buffers assigned to the
Tx FIFO is configured by the MCAN_TXBC[29-24] TFQS field
If the MCAN_TXBC[29-24] 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[12-8] TFGI field)
- Buffer with lowest Message ID gets highest priority and is transmitted next
Figure 12-2743 shows Mixed Dedicated Tx Buffers/Tx FIFO example.