38.6.6.5 Mixed Dedicated Tx Buffers / Tx FIFO

In this case the Tx Buffers section in the Message RAM is subdivided into a set of Dedicated Tx Buffers and a Tx FIFO. The number of Dedicated Tx Buffers is configured by TXBC.NDTB. The number of Tx Buffers assigned to the Tx FIFO is configured by TXBC.TFQS. In case TXBC.TFQS is programmed to zero, only Dedicated Tx Buffers are used.

Figure 38-10. Example of mixed Configuration Dedicated Tx Buffers / Tx FIFO

Tx prioritization:

  • Scan Dedicated Tx Buffers and oldest pending Tx FIFO Buffer (referenced by TXFS.TFGI)
  • Buffer with lowest Message ID gets highest priority and is transmitted next