39.9.5 Standard Message ID Filter Element

Up to 128 filter elements can be configured for 11-bit standard IDs. When accessing a Standard Message ID Filter element, its address is the Filter List Standard Start Address SIDFC.FLSSA plus the index of the filter element (0 ... 127).

Table 39-12. Standard Message ID Filter Element
313029282726252423222120191817161514131211109876543210
S0SFT

[1:0]

SFEC

[2:0]

SFID1[10:0]SFID2[10:0]

  • Bits 31:30 - SFT[1:0]: Standard Filter Type

    This field defines the standard filter type.

    Table 39-13. Standard Filter Type
    ValueNameDescription
    0x0RANGERange filter from SFID1 to SFID2 (SFID2 >= SFID1)
    0x1DUALDual ID filter for SFID1 or SFID2
    0x2CLASSICClassic filter: SFID1 = filter, SFID2 = mask
    0x3RESReserved

  • Bits 29:27 - SFEC[2:0]: Standard Filter Element Configuration

    All enabled filter elements are used for acceptance filtering of standard frames. Acceptance filtering stops at the first matching enabled filter element or when the end of the filter list is reached. If SFEC = “100”, “101”, or “110” a match sets interrupt flag IR.HPM and, if enabled, an interrupt is generated. In this case register HPMS is updated with the status of the priority match.

    Table 39-14. Standard Filter Element Configuration
    ValueNameDescription
    0x0DISABLEDisable filter element
    0x1STF0MStore in Rx FIFO 0 if filter matches
    0x2STF1MStore in Rx FIFO 1 if filter matches
    0x3REJECTReject ID if filter matches
    0x4PRIORITYSet priority if filter matches.
    0x5PRIF0MSet priority and store in FIFO 0 if filter matches.
    0x6PRIF1MSet priority and store in FIFO 1 if filter matches.
    0x7STRXBUFStore into Rx Buffer or as debug message, configuration of SFT[1:0] ignored.

  • Bits 26:16 - SFID1[10:0]: Standard Filter ID 1

    First ID of standard ID filter element.

    When filtering for Rx Buffers or for debug messages this field defines the ID of a standard mesage to be stored. The received identifiers must match exactly, no masking mechanism is used.

  • Bits 15:11 - Reserved

  • Bits 10:0 - SFID2[10:0]: Standard Filter ID 2

    This bit field has a different meaning depending on the configuration of SFEC.


    1. SFEC = “001” ... “110”: Second ID of standard ID filter element.

    2. SFEC = “111”: Filter for Rx Buffers or for debug messages.

    SFID2[10:9] decides whether the received message is stored into an Rx Buffer or treated as message A, B, or C of the debug message sequence.


    00 = Store message into an Rx Buffer


    01 = Debug Message A


    10 = Debug Message B


    11 = Debug Message C

    SFID2[8:6] is Reserved.

    SFID2[5:0] defines the offset to the Rx Buffer Start Address RXBC.RBSA for storage of a matching message.