PXN20RM Datasheet, PDF (729/1376 Pages) Freescale Semiconductor, Inc – PXN20 Microcontroller

FlexRay Communication Controller (FlexRAY)
Commit Side
Transmit Side
Message Buffer Header Field: Frame Header
Message Buffer Header Field: Frame Header
CFG
Message Buffer Header Field: Data Field Offset
CFG
Message Buffer Header Field: Data Field Offset
MBIDXR(2n)[MBIDX]
ITX
MBIDXR(2n+1)]MBIDX]
TX
MSG
MBCCSR(2n)[CMT]
Message Buffer Data Field: DATA[0-N]
MBCCSR(2n+1)[CMT]
Message Buffer Data Field: DATA[0-N]
Message Buffer Header Field: Slot Status
SS
Message Buffer Header Field: Slot Status
SS
MBCCSR(2n)[MBT/MTD]
MBCCFR(2n)[MTM/CHA/CHB/CCF*]
MBFIDR(2n)[FID]
MBCCSR(2n+1)[MBT/MTD]
MBCCFR(2n+1)[MTM/CHA/CHB/CCF*]
SR
MBFIDR(2n+1)[FID]
Figure 26-131. Double Transmit Message Buffer Access Regions Layout
Table 26-106. Double Transmit Message Buffer Access Regions Description
Access
Description
Region
CFG
MSG
ITX
SS
CFG
SR
TX
SS
Type
Application
Module
read/write
read/write
—
—
read/write
—
—
—
—
—
read/write
write-only
—
read-only
read-only
write-only
Commit Side
Message Buffer Configuration
Message Buffer Data and Control access
Internal Message Transfer.
Slot Status Update
Transmit Side
Message Buffer Configuration
Message Buffer Search
Internal Message Transfer, Message Transmission
Slot Status Update
The trigger bits MBCCSRn[EDT] and MBCCSRn[LCKT], and the interrupt enable bit
MBCCSRn[MBIE] are not under access control and can be accessed from the application at any time. The
status bits MBCCSRn[EDS] and MBCCSRn[LCKS] are not under access control and can be accessed
from the controller at any time.
The interrupt flag MBCCSRn.MBIF is not under access control and can be accessed from the application
and the controller at any time. controller set access has higher priority.
The controller restricts its access to the regions, depending on the current state of the corresponding part
of the double transmit message buffer. The application must adhere to these restrictions in order to ensure
data consistency. The states for the commit side of a double transmit message buffer are given in
Figure 26-132. A description of the states is given in Table 26-108. The states for the transmit side of a
Freescale Semiconductor
PXN20 Microcontroller Reference Manual, Rev. 1
26-115