FlexRay Module (FLEXRAYV4)
MFR4310 Reference Manual, Rev. 2
Freescale Semiconductor 189
the Sync Frame Counter Register (SFCNTR). The value in the SFTCCSR.CYCNUM field provides the
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 fields. The application can now start to read the sync table data from the locations given
in Figure 3-134.
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
are reset when the counter values in the Sync Frame Counter Register (SFCNTR) are updated. This is done
because the tables stored in the FRM are no longer related to the values in the Sync Frame Counter Register
(SFCNTR).
Figure 3-135. Sync Frame Table Trigger and Generation Timing
3.4.12.5 Sync Frame Table Access
The sync frame tables is transferred into the FRM during the table write windows shown in Figure 3-135.
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.
3.4.12.5.1 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
the Sync Frame Table Configuration, Control, Status Register (SFTCCSR). If the affected table is not
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.
3.4.13 MTS Generation
The FlexRay module provides a flexible 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 configure the set of communication cycles in which the MTS is transmitted over the
FlexRay bus by programming the CYCCNTMSK and CYCCNTVAL fields in the MTS A Configuration
Register (MTSACFR) and MTS B Configuration Register (MTSBCFR).
SFTCCSR.[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
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