Module Operation
1233
SPNU563A – March 2018
Copyright © 2018, Texas Instruments Incorporated
FlexRay Module
To leave CONFIG state, the host has to perform the unlock sequence. Directly after unlocking the
CONFIG state the host has to write SUCC1.CMD(3-0) to enter the next state.
NOTE:
The message buffer status registers (MHDS, TXRQ1/2/3/4, NDAT1/2/3/4, MBSC1/2/3/4) and
status data stored in the message RAM and are not affected by the transition of the POC
from CONFIG to READY state.
When the communication controller is in CONFIG state it is also possible to bring the communication
controller into a power saving mode by halting the module clocks. To do this the host has to assure that all
Message RAM transfers have finished before turning off the clocks.
26.2.6.4 MONITOR_MODE
After unlocking CONFIG state and writing SUCC1.CMD(3-0) = 1011 the communication controller enters
MONITOR_MODE. In this mode the communication controller is able to receive FlexRay frames and to
detect wakeup pattern. The temporal integrity of received frames is not checked, and therefore cycle
counter filtering is not supported. This mode can be used for debugging purposes in case e.g. that startup
of a FlexRay network fails. After writing SUCC1.CMD(3-0) = 0001 the communication controller transits
back to CONFIG state.
In MONITOR_MODE the pick first valid mechanism is disabled. This means that a receive message buffer
may only be configured to receive on one channel. Received frames are stored into message buffers
according to frame ID and receive channel. Null frames are handled like data frames. After frame
reception only status bits MBS.VFRA, MBS.VFRB, MBS.MLST, MBS.RCIS, MBS.SFIS, MBS.SYNS,
MBS.NFIS, MBS.PPIS, MBS.RESS have valid values.
In MONITOR_MODE the communication controller is not able to distinguish between CAS and MTS
symbols. In case one of these symbols is received on one or both of the two channels, the flags
SIR.MTSA/SIR.MTSB are set. SIR.CAS has no function in MONITOR_MODE.
26.2.6.5 READY State
After unlocking CONFIG state and writing SUCC1.CMD(3-0) = 0010 the communication controller enters
READY state. From this state the communication controller can transit to WAKEUP state and perform a
cluster wakeup or to STARTUP state to perform a coldstart or to integrate into a running cluster.
The communication controller enters this state:
•
When exiting from CONFIG, WAKEUP, STARTUP, NORMAL_ACTIVE, or NORMAL_PASSIVE state
by writing SUCC1.CMD(3-0) = 0010 (READY command).
The communication controller exits from this state:
•
To CONFIG state by writing SUCC1.CMD(3-0) = 0001 (CONFIG command)
•
To WAKEUP state by writing SUCC1.CMD(3-0) = 0011 (WAKEUP command)
•
To STARTUP state by writing SUCC1.CMD(3-0) = 0100 (RUN command)
Internal counters and the communication controller status flags are reset when the communication
controller enters STARTUP state.
NOTE:
Status bits MHDS(14-0), registers TXRQ1/2/3/4, and status data stored in the Message RAM
are not affected by the transition of the POC from READY to STARTUP state.