![NXP Semiconductors freescale KV4 Series Reference Manual Download Page 1143](http://html1.mh-extra.com/html/nxp-semiconductors/freescale-kv4-series/freescale-kv4-series_reference-manual_17217891143.webp)
43.5.5.2 Move-out
The move-out process is the copy of the content from a Tx Mailbox to the Tx SMB when
a message for transmission is available (see Section "Arbitration process"). The move-out
occurs in the following conditions:
• The first bit of Intermission field
• During Bus Off state when TX Error Counter is in the 124 to 128 range
• During Bus Idle state
• During Wait For Bus Idle state
The move-out process is not atomic. Only the CPU has priority to access the memory
concurrently out of Bus Idle state. In Bus Idle, the move-out has the lowest priority to the
concurrent memory accesses.
43.5.6 Data coherence
In order to maintain data coherency and FlexCAN proper operation, the CPU must obey
the rules described in
.
43.5.6.1 Transmission abort mechanism
The abort mechanism provides a safe way to request the abortion of a pending
transmission. A feedback mechanism is provided to inform the CPU if the transmission
was aborted or if the frame could not be aborted and was transmitted instead.
Two primary conditions must be fulfilled in order to abort a transmission:
• CAN_MCR[AEN] bit must be asserted
• The first CPU action must be the writing of abort code (0b1001) into the CODE field
of the Control and Status word.
Active MBs configured for transmission must be aborted first before they can be updated.
If the abort code is written to a Mailbox that is currently being transmitted or to a
Mailbox that was already loaded into the Tx SMB for transmission, the write operation is
blocked and the transmission is not disturbed. However, the abort request is captured and
kept pending until one of the following conditions is satisfied:
• The module loses the bus arbitration
• There is an error during the transmission
Chapter 43 Flex Controller Area Network (FlexCAN)
KV4x Reference Manual, Rev. 2, 02/2015
Freescale Semiconductor, Inc.
Preliminary
1143
Summary of Contents for freescale KV4 Series
Page 2: ...KV4x Reference Manual Rev 2 02 2015 2 Preliminary Freescale Semiconductor Inc...
Page 60: ...KV4x Reference Manual Rev 2 02 2015 60 Preliminary Freescale Semiconductor Inc...
Page 128: ...Debug Security KV4x Reference Manual Rev 2 02 2015 128 Preliminary Freescale Semiconductor Inc...
Page 138: ...Boot KV4x Reference Manual Rev 2 02 2015 138 Preliminary Freescale Semiconductor Inc...
Page 1358: ...KV4x Reference Manual Rev 2 02 2015 1358 Preliminary Freescale Semiconductor Inc...