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MFR4200 FlexRay Communication Controller
MFR4200 Data Sheet, Rev. 0
162
Freescale Semiconductor
NOTE
Figure 3-131
does not apply to message buffers configured as receive FIFO
buffers.
3.5.3.2
Active Transmit Message Buffer
The active transmit message buffer (see
Table 3-1
) contains transmit message buffer data and configuration
fields. Any transmit message buffer is accessible through the active transmit message buffer after the buffer
has been locked successfully. The active transmit message buffer layout is shown in
Table 3-13
.
Buffer control, configuration, filtering and status data is stored in the buffer control, configuration, status
and filtering registers set. The layout of the set is presented in
Figure 3-131
.
3.5.3.3
Active Receive FIFO Buffer
The active receive FIFO message buffer (see
Table 3-1
) contains receive FIFO buffer data and
configuration fields. Any receive FIFO buffer is accessible through the active receive FIFO buffer after the
locking procedure for this buffer has been finished.
For a detailed description of FIFO access, refer to
Section 3.6, “Receive FIFO Function
”. The active
receive FIFO buffer layout is shown in
Table 3-12
. The locking procedure for receive FIFO buffers is
different from the receive/transmit message buffer locking operation (see
Section 3.5.3.4, “Active Buffers
Locking/Unlocking and Locking Timing
” and the LOCK bit description in
Section 3.2.3.7.2, “Message
Buffer Control, Configuration and Status n Register, n = [0:58] (BUFCSnR)
”).
NOTE
Figure 3-131
is applicable for transmit and receive message buffers only, not
for receive FIFO buffers.
If a buffer is configured as a receive FIFO buffer, only its buffer control, configuration and status register
(BUFCSnR) is used; the CCFnR registers are not. Instead of the CCFnR registers, the FIFO acceptance
filter registers and FIFO rejection filter registers must be used.
The buffer control, configuration, status and filtering register set for the receive FIFO buffers is shown on
the
Figure 3-132
. Buffer 0 is configured as a receive FIFO buffer.