FlexRay Module (FLEXRAYV4)
MFR4310 Reference Manual, Rev. 2
190 Freescale Semiconductor
The application enables or disables the generation of the MTS on either channel by setting or clearing the
MTE control bit in the MTS A Configuration Register (MTSACFR) or MTS B Configuration Register
(MTSBCFR). If an MTS is to be transmitted in a certain communication cycle, the application must set
the MTE control bit during the static segment of the preceding communication cycle.
The MTS is transmitted over channel A in the communication cycle with number CYCCNT, if
Equation 3-16, Equation 3-17, and Equation 3-17 are fulfilled.
Eqn. 3-15
Eqn. 3-16
Eqn. 3-17
The MTS is transmitted over channel B in the communication cycle with number CYCCNT, if
Equation 3-15, Equation 3-18, and Equation 3-19 are fulfilled.
Eqn. 3-18
Eqn. 3-19
3.4.14 Sync Frame and Startup Frame Transmission
The transmission of sync frames and startup frames is controlled by the following register fields:
• PCR18.key_slot_id: provides the number of the slot for sync or startup frame transmission
• PCR11.key_slot_used_for_sync: indicates sync frame transmission
• PCR11.key_slot_used_for_startup: indicates startup frame transmission
• PCR12.key_slot_header_crc: provides header crc for sync frame or startup frame
• Message buffer with message buffer number n=PCR18.key_slot_id
The generation of the sync or startup frames depends on the current protocol state. In the POC:startup
state, the generation is independent of the message buffer setup; in the POC:normal active state, the
generation is affected by the current message buffer setup.
3.4.14.1 Sync Frame and Startup Frame Transmission in POC:startup
In the POC:startup state, the sync and startup frame transmission is independent of the message buffer
setup. If at least one of the indication bits PCR11.key_slot_used_for_sync or
PCR11.key_slot_used_for_startup is set, a Null Frame is transmitted in the slot with slot number
PCR18.key_slot_id. The header CRC for this Null Frame is taken from PCR12.key_slot_header_crc. The
settings of the sync and startup frame indicators are taken from PCR11.key_slot_used_for_sync and
PCR11.key_slot_used_for_startup.
3.4.14.2 Sync Frame and Startup Frame Transmission in POC:normal active
In the POC:normal active state, the sync and startup frame transmission depends on the message buffer
setup. If at least one of the indication bits PCR11.key_slot_used_for_sync or
PSR0 PROTSTATE[]POC:normal active=
CYCCNT MTSACFR CYCCNTMSK[]∧ MTSACFR CYCCNTVAL[]MTSACFR CYCCNTMSK[]∧=
CYCCNT MTSBCFR CYCCNTMSK[]∧ MTSBCFR CYCCNTVAL[]MTSBCFR CYCCNTMSK[∧=
To Next Page
Loading...