PXS20RM Datasheet, PDF (843/1368 Pages) Freescale Semiconductor, Inc – PXS20 Microcontroller

FlexRay Communication Controller
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
FR_MBIDXR(2n)[MBIDX]
ITX
FR_MBIDXR(2n+1)]MBIDX]
TX
MSG
FR_MBCCSR(2n)[CMT]
Message Buffer Data Field: DATA[0-N]
FR_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
FR_MBCCSR(2n)[MBT/MTD]
FR_MBCCFR(2n)[MTM/CHA/CHB/CCF*]
FR_MBFIDR(2n)[FID]
FR_MBCCSR(2n+1)[MBT/MTD]
FR_MBCCFR(2n+1)[MTM/CHA/CHB/CCF*]
SR
FR_MBFIDR(2n+1)[FID]
Figure 26-141. Double Transmit Message Buffer Access Regions Layout
Table 26-116. 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 FR_MBCCSRn[EDT] and FR_MBCCSRn[LCKT], and the interrupt enable bit
FR_MBCCSRn[MBIE] are not under access control and can be accessed from the application at any time.
The status bits FR_MBCCSRn[EDS] and FR_MBCCSRn[LCKS] are not under access control and can be
accessed from the CC at any time.
The interrupt flag FR_MBCCSRn[MBIF] is not under access control and can be accessed from the
application and the CC at any time. CC set access has higher priority.
The CC 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 26-142.
A description of the states is given in Table 26-118. The states for the transmit side of a double transmit
Freescale Semiconductor
PXS20 Microcontroller Reference Manual, Rev. 1
26-131