FlexRay Communication Controller (FLEXRAY)
MPC5510 Microcontroller Family Reference Manual, Rev. 1
30-98
Freescale Semiconductor
Preliminary
MBCCSRn.EDS and MBCCSRn.LCKS are not under access control and can be accessed from the
FlexRay block at any time.
The interrupt flag MBCCSnR.MBIF is not under access control and can be accessed from the application
and the FlexRay block at any time. FlexRay block clear access has higher priority.
The FlexRay block restricts its access to the regions depending on the current state of the message buffer.
The application must adhere to these restrictions in order to ensure data consistency. The transmit message
buffer states are given in
. A description of the states is given in
provides the access scheme for the access regions.
The status bits MBCCSRn.EDS and MBCCSRn.LCKS provide the application with the required message
buffer status information. The internal status information is not visible to the application.
30.6.6.2.2
Message Buffer States
This section describes the transmit message buffer states and provides a state diagram.
Figure 30-113. Single Transmit Message Buffer States
Table 30-93. Single Transmit Message Buffer State Description (Sheet 1 of 2)
State
MBCCSRn
Access Region
Description
EDS
LCKS
Appl.
Module
Idle
1
0
–
CM,
SR
Idle - Message Buffer is idle.
Included in message buffer search.
HDis
0
0
CFG
–
Disabled - Message Buffer under configuration.
Excluded from message buffer search.
HDisLck
0
1
CFG
–
Disabled and Locked - Message Buffer under configuration.
Excluded from message buffer search.
HLck
1
1
MSG
SR
Locked - Applications access to data, control, and status.
Included in message buffer search.
HLckCCSa
HL
HLck
HDisLck
HDis
Idle
CCTx
HE
HLckCCMa
SA
CCSa
CCMa
SA
MA
TX
RESET_STATE
DSS
DSS
CCNf
SSS
STS
HLckCCNf
STS
SSS
STS
HU
HD
HL
HU
HL
HU
HL
HU
HL
HU
HE
HD
STS
CCSu
SU
SSS
DSS
DSS
MA