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Chapter 13 FlexRay Communication Controller (FLEXRAY)
MC9S12XF - Family Reference Manual, Rev.1.19
Freescale Semiconductor
595
number of the cycle that this table is related to.
The number of available table entries per channel is provided in the SFCNTR.SFEVA and
SFCNTR.SFEVB elds. The application can now start to read the sync table data from the locations given
After reading all the data from the locked tables, the application must unlock the table by writing to the
even table lock trigger SFTCCSR.ELKT again. The even table lock status bit SFTCCSR.ELKS is reset
immediately.
If the sync frame table generation is disabled, the table valid bits SFTCCSR.EVAL and SFTCCSR.EVAL
Figure 13-139. Sync Frame Table Trigger and Generation Timing
13.6.12.5 Sync Frame Table Access
The sync frame tables will be transferred into the FRM during the table write windows shown in
Figure 13-139. During the table write, the application can not lock the table that is currently written. If the application
locks the table outside of the table write window, the lock is granted immediately.
13.6.12.5.1
Sync Frame Table Locking and Unlocking
The application locks the even/odd sync frame table by writing 1 to the lock trigger bit ELKT/OLKT in
currently written to the FRM, the lock is granted immediately, and the lock status bit ELKS/OLKS is set.
If the affected table is currently written to the FRM, the lock is not granted. In this case, the application
must issue the lock request again until the lock is granted.
The application unlocks the even/odd sync frame table by writing 1 to the lock trigger bit ELKT/OLKT.
The lock status bit ELKS/OLKS is cleared immediately.
13.6.13 MTS Generation
The FlexRay block provides a exible means to request the transmission of the Media Access Test Symbol
MTS in the symbol window on channel A or channel B.
The application can congure the set of communication cycles in which the MTS will be transmitted over
the FlexRay bus by programming the CYCCNTMSK and CYCCNTVAL elds in the
MTS ASFTCCSR.[OPT,SIDEN,SDVEN] write window
even table write
static segment
NIT
static segment
NIT
static segment
NIT
cycle 2n-1
cycle 2n
cycle 2n+1
odd table write