
FlexRay Communication Controller (FlexRay)
MPC5644A Microcontroller Reference Manual, Rev. 6
1592
Freescale Semiconductor
33.6.12.4 Sync frame ID and sync frame deviation table generation
The application controls the generation process of the Sync Frame ID and Sync Frame Deviation Tables
into the FlexRay memory area using the
Sync Frame Table Configuration, Control, Status Register
. A summary of the copy modes is given in
.
The Sync Frame Table generation process is described in the following for the even cycle. The same
sequence applies to the odd cycle.
If the application has enabled the sync frame table generation by setting FR_SFTCCSR[SIDEN] to 1, the
CC starts the update of the even cycle related tables after the start of the NIT of the next even cycle. The
CC checks if the application has locked the tables by reading the FR_SFTCCSR[ELKS] lock status bit. If
this bit is set, the CC will not update the table in this cycle. If this bit is cleared, the CC locks this table and
starts the table update. To indicate that these tables are currently updated and may contain inconsistent
data, the CC clears the even table valid status bit FR_SFTCCSR[EVAL]. Once all table entries related to
the even cycle have been transferred into the FlexRay memory area, the CC sets the even table valid bit
FR_SFTCCSR[EVAL] and the Even Cycle Table Written Interrupt Flag EVT_IF in the
. If the interrupt enable flag EVT_IE is set, an interrupt request is generated.
To read the generated tables, the application must lock the tables to prevent the CC from updating these
tables. The locking is initiated by writing a 1 to the even table lock trigger FR_SFTCCSR[ELKT]. When
the even table is not currently updated by the CC, the lock is granted and the even table lock status bit
FR_SFTCCSR[ELKS] is set. This indicates that the application has successfully locked the even sync
tables and the corresponding status information fields SFRA, SFRB in the
. The value in the FR_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 FR_SFCNTR[SFEVA] and
FR_SFCNTR[SFEVB] fields. The application can now start to read the sync table data from the locations
given in
.
Table 33-124. Sync frame table generation modes
FR_SFTCCSR
Description
OPT
SDVEN
SIDEN
0
0
0
No Sync Frame Table copy
0
0
1
Sync Frame ID Tables will be copied continuously
0
1
0
Reserved
0
1
1
Sync Frame ID Tables and Sync Frame Deviation Tables will be copied continuously
1
0
0
No Sync Frame Table copy
1
0
1
Sync Frame ID Tables for next even-odd-cycle pair will be copied
1
1
0
Reserved
1
1
1
Sync Frame ID Tables and Sync Frame Deviation Tables for next even-odd-cycle
pair will be copied
Summary of Contents for MPC5644A
Page 2: ...MPC5644A Microcontroller Reference Manual Rev 6 2 Freescale Semiconductor...
Page 24: ...MPC5644A Microcontroller Reference Manual Rev 6 24 Freescale Semiconductor...
Page 26: ...MPC5644A Microcontroller Reference Manual Rev 6 26 Freescale Semiconductor...
Page 52: ...Introduction MPC5644A Microcontroller Reference Manual Rev 6 52 Freescale Semiconductor...
Page 56: ...Memory Map MPC5644A Microcontroller Reference Manual Rev 6 56 Freescale Semiconductor...
Page 1228: ...Decimation Filter MPC5644A Microcontroller Reference Manual Rev 6 1228 Freescale Semiconductor...
Page 1440: ...FlexCAN Module MPC5644A Microcontroller Reference Manual Rev 6 1440 Freescale Semiconductor...