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45.4.5 Move process
There are two types of move process: move-in and move-out.
45.4.5.1 Move-in
The move-in process is the copy of a message received by an Rx SMB to a Rx Mailbox
or FIFO that has matched it. If the move destination is the Rx FIFO, attributes of the
message are also copied to the RXFIR FIFO. Each Rx SMB has its own move-in process,
but only one is performed at a given time as described ahead. The move-in starts only
when the message held by the Rx SMB has a corresponding matching winner (see
Matching process) and all of the following conditions are true:
• The CAN bus has reached or let past either:
• The second bit of Intermission field next to the frame that carried the message
that is in the Rx SMB
• The first bit of an overload frame next to the frame that carried the message that
is in the Rx SMB
• There is no ongoing matching process
• The destination Mailbox is not locked by the CPU
• There is no ongoing move-in process from another Rx SMB. If more than one move-
in processes are to be started at the same time both are performed and the newest
substitutes the oldest.
The term pending move-in is used throughout the documentation and stands for a move-
to-be that still does not satisfy all of the aforementioned conditions.
The move-in is cancelled and the Rx SMB is able to receive another message if any of
the following conditions is satisfied:
• The destination Mailbox is inactivated after the CAN bus has reached the first bit of
Intermission field next to the frame that carried the message and its matching process
has finished
• There is a previous pending move-in to the same destination Mailbox
• The Rx SMB is receiving a frame transmitted by the FlexCAN itself and the self-
reception is disabled (MCR[SRXDIS] bit is asserted)
• Any CAN protocol error is detected
Note that the pending move-in is not cancelled if the module enters Freeze or Low-Power
mode. It only stays on hold waiting for exiting Freeze and Low-Power mode and to be
unlocked. If an MB is unlocked during Freeze mode, the move-in happens immediately.
Functional description
K20 Sub-Family Reference Manual, Rev. 1.1, Dec 2012
1160
Preliminary
Freescale Semiconductor, Inc.
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