Freescale Semiconductor FlexRay MFR4310 - Table 3-92. Single Transmit Message Buffer Application Transitions

FlexRay Module (FLEXRAYV4)
MFR4310 Reference Manual, Rev. 2
Freescale Semiconductor 155
3.4.6.2.3 Message Buffer Transitions
Application Transitions
The application transitions can be triggered by the application using the commands described in
Table 3-92. The application issues the commands by writing to the Message Buffer Configuration,
Control, Status Registers (MBCCSRn). Only one command can be issued with one write access. Each
command is executed immediately. If the command is ignored, it must be issued again.
The enable and disable commands issued by writing 1 to the trigger bit MBCCSRn.EDT. The transition
that triggered by each of these command depends on the current value of the status bit MBCCSRn.EDS.
If the command triggers the disable transition HD and the message buffer is in one of the states CCSa,
HLckCCSa, CCMa, HLckCCMa, CCNf, HLckCCNf, or CCTx, the disable transition has no effect
(command is ignored) and the message buffer state is not changed. No notification is given to the
application.
The lock and unlock commands issued by writing 1 to the trigger bit MBCCSRn.LCKT. The transition that
triggered by each of these commands depends on the current value of the status bit MBCCSRn.LCKS. If
the command triggers the lock transition HL and the message buffer is in the state CCTx, the lock
transition has no effect (command is ignored) and message buffer state is not changed. In this case, the
message buffer lock error flag LCK_EF in the CHI Error Flag Register (CHIERFR) is set.
CCSa 10––Slot Assigned - Message buffer assigned to next static slot.
Ready for Null Frame transmission.
HLckCCSa 1 1 MSG – L
ocked and Slot Assigned - Applications access to data, control,
and status.Message buffer assigned to next static slot
CCNf 1 0 – NF Null Frame Transmission
Header is used for null frame transmission.
HLckCCNf 1 1 MSG NF Locked and Null Frame Transmission - Applications access to
data, control, and status. Header is used for null frame transmission.
CCMa 1 0 – CM M
essage Available - Message buffer is assigned to next slot and
cycle counter filter matches.
HLckCCMa 1 1 MSG – Locked and Message Available - Applications access to data,
control, and status. Message buffer is assigned to next slot and cycle
counter filter matches.
CCTx 10–TXMessage Transmission - Message buffer data transmit. Payload
data from buffer transmitted
CCSu 1 0 – TX Status Update - Message buffer status update. Update of status
flags, the slot status field, and the header index.
Table 3-92. Single Transmit Message Buffer Application Transitions
Transition Command Condition Description
HE
MBCCSRn.EDT:= 1
MBCCSRn.EDS = 0 Application triggers message buffer enable.
HD MBCCSRn.EDS = 1 Application triggers message buffer disable.
Table 3-91. Single Transmit Message Buffer State Description (Continued)
State
MBCCSRn Access Region
Description
EDS LCKS Appl. Module