Datasheet

ManualsBrandsMicrochip ManualsARM MicrocontrollersARM SAM Microcontroller 2MB LQFP

1421

49.5.7.2 Rx Buffer and FIFO Element

Up to 64 Rx Buffers and two Rx FIFOs can be configured in the Message RAM. Each Rx FIFO section can be

configured to store up to 64 received messages. The structure of a Rx Buf

fer / FIFO element is shown in the table

below. The element size can be configured for storage of CAN FD messages with up to 64 bytes data field via

Table 49-7. Rx Buffer and FIFO Element

31 24 23 16 15 8 7 0

R0 ESI XTD RTR ID[28:0]

R1 ANMF FIDX[6:0] – FDF BRS DLC[3:0] RXTS[15:0]

R2 DB3[7:0] DB2[7:0] DB1[7:0] DB0[7:0]

R3 DB7[7:0] DB6[7:0] DB5[7:0] DB4[7:0]

... ... ... ... ...

Rn DBm[7:0] DBm-1[7:0] DBm-2[7:0] DBm-3[7:0]

• R0 Bit 31 ESI: Error State Indicator

0: T

ransmitting node is error active.

1: Transmitting node is error passive.

• R0 Bit 30 XTD: Extended Identifier

Signals to the processor whether the received frame has a standard or extended identifier.

0: 11-bit standard identifier.

1: 29-bit extended identifier.

• R0 Bit 29 RTR: Remote Transmission Request

Signals to the processor whether the received frame is a data frame or a remote frame.

0: Received frame is a data frame.

1: Received frame is a remote frame.

Note: There are no remote frames in CAN FD format. In case a CAN FD frame was received (FDF = 1), bit RTR

reflects the state of the reserved bit r1.

• R0 Bits 28:0 ID[28:0]: Identifier

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

• R1 Bit 31 ANMF: Accepted Non-matching Frame

Acceptance of non-matching frames may be enabled via MCAN_GFC.ANFS and MCAN_GFC.ANFE.

0: Received frame matching filter index FIDX.

1: Received frame did not match any Rx filter element.

• R1 Bits 30:24 FIDX[6:0]: Filter Index

0-127: Index of matching Rx acceptance filter element (invalid if ANMF = ‘1’).

Range is 0 to MCAN_SIDFC.LSS - 1 resp. MCAN_XIDFC.LSE - 1.

• R1 Bit 21 FDF: FD Format

0: Standard frame format.

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

• R1 Bit 20 BRS: Bit Rate Switch

0: Frame received without bit rate switching.

SAM E70/S70/V70/V71 Family

Controller Area Network (MCAN)

echnology Inc.

Datasheet

DS60001527D-page 1424