
During the arbitration phase the delay compensation is always disabled. The maximum
delay which can be compensated by the FlexCAN's transceiver delay compensation
during the data phase is 3 CAN bit times – 2 Tq. Beyond this limit, the
FDCTRL[TDCFAIL] flag is set to indicate when the transceiver delay compensation
mechanism is out of range, unable to compensate the transceiver loop delay.
49.5.9.4 Remote frames
A remote frame is a special kind of frame. You can program a mailbox to be a remote
request frame by configuring the mailbox as Transmit with the RTR bit set to one. After
the remote request frame is transmitted successfully, the mailbox becomes a receive
message buffer, with the same ID as before.
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]):
• 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.
Functional description
MWCT101xS Series Reference Manual, Rev. 3, 07/2019
1690
NXP Semiconductors
Содержание MWCT101 S Series
Страница 2: ...MWCT101xS Series Reference Manual Rev 3 07 2019 2 NXP Semiconductors...
Страница 42: ...MWCT101xS Series Reference Manual Rev 3 07 2019 42 NXP Semiconductors...
Страница 50: ...Conventions MWCT101xS Series Reference Manual Rev 3 07 2019 50 NXP Semiconductors...
Страница 70: ...Aliased bit band regions MWCT101xS Series Reference Manual Rev 3 07 2019 70 NXP Semiconductors...
Страница 78: ...Pinout diagrams MWCT101xS Series Reference Manual Rev 3 07 2019 78 NXP Semiconductors...
Страница 96: ...WCT101xS safety concept MWCT101xS Series Reference Manual Rev 3 07 2019 96 NXP Semiconductors...
Страница 130: ...Functional description MWCT101xS Series Reference Manual Rev 3 07 2019 130 NXP Semiconductors...
Страница 200: ...Initialization application information MWCT101xS Series Reference Manual Rev 3 07 2019 200 NXP Semiconductors...
Страница 284: ...Functional description MWCT101xS Series Reference Manual Rev 3 07 2019 284 NXP Semiconductors...
Страница 430: ...Functional Description MWCT101xS Series Reference Manual Rev 3 07 2019 430 NXP Semiconductors...
Страница 472: ...Application Information MWCT101xS Series Reference Manual Rev 3 07 2019 472 NXP Semiconductors...
Страница 508: ...Reset memory map and register descriptions MWCT101xS Series Reference Manual Rev 3 07 2019 508 NXP Semiconductors...
Страница 528: ...Module clocks MWCT101xS Series Reference Manual Rev 3 07 2019 528 NXP Semiconductors...
Страница 634: ...SRAM configuration MWCT101xS Series Reference Manual Rev 3 07 2019 634 NXP Semiconductors...
Страница 696: ...Initialization and application information MWCT101xS Series Reference Manual Rev 3 07 2019 696 NXP Semiconductors...
Страница 818: ...Functional description MWCT101xS Series Reference Manual Rev 3 07 2019 818 NXP Semiconductors...
Страница 960: ...Functional description MWCT101xS Series Reference Manual Rev 3 07 2019 960 NXP Semiconductors...
Страница 970: ...Memory Map and Register Definition MWCT101xS Series Reference Manual Rev 3 07 2019 970 NXP Semiconductors...
Страница 992: ...ADC calibration scheme MWCT101xS Series Reference Manual Rev 3 07 2019 992 NXP Semiconductors...
Страница 1118: ...Application information MWCT101xS Series Reference Manual Rev 3 07 2019 1118 NXP Semiconductors...
Страница 1294: ...Initialization Procedure MWCT101xS Series Reference Manual Rev 3 07 2019 1294 NXP Semiconductors...
Страница 1348: ...Functional description MWCT101xS Series Reference Manual Rev 3 07 2019 1348 NXP Semiconductors...
Страница 1366: ...Functional description MWCT101xS Series Reference Manual Rev 3 07 2019 1366 NXP Semiconductors...
Страница 1514: ...Functional description MWCT101xS Series Reference Manual Rev 3 07 2019 1514 NXP Semiconductors...
Страница 1726: ...Debug and security MWCT101xS Series Reference Manual Rev 3 07 2019 1726 NXP Semiconductors...
Страница 1740: ...Initialization application information MWCT101xS Series Reference Manual Rev 3 07 2019 1740 NXP Semiconductors...
Страница 1760: ...MWCT101xS Series Reference Manual Rev 3 07 2019 1760 NXP Semiconductors...