When a remote request frame is received by FlexCAN, it can be treated in three ways,
depending on Remote Request Storing (CTRL2[RRS]) and Rx FIFO Enable
(MCR[RFEN]) bits:
• If RRS is negated the frame's ID is compared to the IDs of the Transmit Message
Buffers with the CODE field 0b1010. If there is a matching ID, then this mailbox
frame will be transmitted. Note that if the matching mailbox has the RTR bit set, then
FlexCAN will transmit a remote frame as a response. The received remote request
frame is not stored in a receive buffer. It is only used to trigger a transmission of a
frame in response. The mask registers are not used in remote frame matching, and all
ID bits (except RTR) of the incoming received frame should match. In the case that a
remote request frame is received and matches a mailbox, this message buffer
immediately enters the internal arbitration process, but is considered as a normal Tx
mailbox, with no higher priority. The data length of this frame is independent of the
DLC field in the remote frame that initiated its transmission.
• If RRS is asserted the frame's ID is compared to the IDs of the receive mailboxes
with the CODE field 0b0100, 0b0010 or 0b0110. If there is a matching ID, then this
mailbox will store the remote frame in the same fashion of a data frame. No
automatic remote response frame will be generated. The mask registers are used in
the matching process.
• If RFEN is asserted FlexCAN will not generate an automatic response for remote
request frames that match the FIFO filtering criteria. If the remote frame matches one
of the target IDs, it will be stored in the FIFO and presented to the CPU. Note that for
filtering formats A and B, it is possible to select whether remote frames are accepted
or not. For format C, remote frames are always accepted (if they match the ID).
Remote Request Frames are considered as normal frames, and generate a FIFO
overflow when a successful reception occurs and the FIFO is already full.
50.5.8.2 Overload frames
FlexCAN does transmit overload frames due to detection of following conditions on
CAN bus:
• Detection of a dominant bit in the first/second bit of Intermission
• Detection of a dominant bit at the 7th bit (last) of End of Frame field (Rx frames)
• Detection of a dominant bit at the 8th bit (last) of Error Frame Delimiter or Overload
Frame Delimiter
Functional description
Kinetis KE1xF Sub-Family Reference Manual, Rev. 4, 06/2019
1454
NXP Semiconductors
Содержание KE1xF Series
Страница 2: ...Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 2 NXP Semiconductors...
Страница 60: ...SysTick Clock Configuration Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 60 NXP Semiconductors...
Страница 114: ...Initialization application information Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 114 NXP Semiconductors...
Страница 138: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 138 NXP Semiconductors...
Страница 320: ...Private Peripheral Bus PPB memory map Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 320 NXP Semiconductors...
Страница 342: ...Functional Description Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 342 NXP Semiconductors...
Страница 360: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 360 NXP Semiconductors...
Страница 490: ...Interrupts Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 490 NXP Semiconductors...
Страница 550: ...Memory map and register definition Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 550 NXP Semiconductors...
Страница 562: ...Boot Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 562 NXP Semiconductors...
Страница 662: ...Power supply supervisor Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 662 NXP Semiconductors...
Страница 694: ...On chip resource access control mechanism Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 694 NXP Semiconductors...
Страница 706: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 706 NXP Semiconductors...
Страница 724: ...Application Information Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 724 NXP Semiconductors...
Страница 736: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 736 NXP Semiconductors...
Страница 750: ...Debug and Security Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 750 NXP Semiconductors...
Страница 798: ...Functional description Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 798 NXP Semiconductors...
Страница 808: ...Functional description Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 808 NXP Semiconductors...
Страница 866: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 866 NXP Semiconductors...
Страница 1164: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 1164 NXP Semiconductors...
Страница 1178: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 1178 NXP Semiconductors...
Страница 1380: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 1380 NXP Semiconductors...
Страница 1472: ...Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 1472 NXP Semiconductors...
Страница 1482: ...Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 1482 NXP Semiconductors...