34.9.4 Tx Event FIFO Element

Each element stores information about transmitted messages. By reading the Tx Event FIFO the Host CPU gets this information in the order the messages were transmitted. Status information about the Tx Event FIFO can be obtained from register TXEFS.

Table 34-10. Tx Event FIFO Element
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
E0 E

S

I

 X

T

D

 R

T

R

 ID[28:0]
E1 MM[7:0] ET

[1:0]

 F

D

F

 B

R

S

 DLC[3:0] TXTS[15:0]

  • E0 Bit 31 - ESI: Error State Indicator

    0 : Transmitting node is error active.

    1 : Transmitting node is error passive.

  • E0 Bit 30 - XTD: Extended Identifier

    0 : 11-bit standard identifier.

    1 : 29-bit extended identifier.

  • E0 Bit 29 - RTR: Remote Transmission Request

    0 : Received frame is a data frame.

    1 : Received frame is a remote frame.

  • E0 Bits 28:0 - ID[28:0]: Identifier

    Standard or extended identifier depending on bit XTD. A standard identifier is stored into ID[28:18].

  • E1 Bits 31:24 - MM[7:0]: Message Marker

    Copied from Tx Buffer into Tx Event FIFO element for identification of Tx message status.

  • E1 Bits 23:22 - ET[1:0]: Event Type

    This field defines the event type.

    Table 34-11. Event Type
    Value Name Description
    0x0 or 0x3 RES Reserved
    0x1 TXE Tx event
    0x2 TXC Transmission in spite of cancellation (always set for transmission in DAR mode)

  • E1 Bit 21 - FDF: FD Format

    0 : Standard frame format.

    1 : CAN FD frame format (new DLC-coding and CRC).

  • E1 Bit 20 - BRS: Bit Rate Search

    0 : Frame received without bit rate switching.

    1 : Frame received with bit rate switching.

  • E1 Bits 19:16 - DLC[3:0]: Data Length Code

    0-8 : CAN + CAN FD: received frame has 0-8 data bytes.

    9-15 : CAN: received frame has 8 data bytes.

    9-15 : CAN FD: received frame has 12/16/20/24/32/48/64 data bytes.

  • E1 Bits 15:0 - TXTS[15:0]: Tx Timestamp

    Timestamp Counter value captured on start of frame transmission. Resolution depending on configuration of the Timestamp Counter Prescaler TSCC.TCP.