Freescale Semiconductor FlexRay MFR4310, Reference Manual

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FlexRay Module (FLEXRAYV4)
MFR4310 Reference Manual, Rev. 2
Freescale Semiconductor 63
• measured value indicators for the clock synchronization
— internal synchronization frame ID and synchronization frame measurement tables can be
copied into the FlexRay Memory
• fractional macroticks are supported for clock correction
• maskable interrupt sources provided via individual and combined interrupt lines
• 1 absolute timer
• 1 timer that can be configured to absolute or relative
3.1.6 Modes of Operation
3.1.6.1 Disabled Mode
This is the default mode the FlexRay module enters during hard reset. The FlexRay module indicates that
it is in the Disabled Mode by negating the FlexRay module enable bit MEN in the
Module Configuration
Register (MCR) .
The protocol engine is in its reset state. No communication is performed on the FlexRay bus.
All registers with the write access conditions Any Time and Disabled Mode can be accessed for writing as
stated in
Section 3.3.2, “Register Descriptions” .
The application can configure the FlexRay module by accessing the FlexRay module configuration bits
and fields in the
Module Configuration Register (MCR) .
The FlexRay module leaves disabled mode when the application sets the FlexRay module enable bit MEN
in the
Module Configuration Register (MCR) The FlexRay module then deasserts the protocol engine reset
and puts the protocol engine into the POC:default config state.
NOTE
After the application has enabled the FlexRay module it cannot disable the
FlexRay module later on.
3.1.6.2 Normal Mode
In this mode the FlexRay module is fully functional.
The FlexRay module indicates that it is in normal mode by asserting the FlexRay module enable bit (MEN)
in the
Module Configuration Register (MCR) .
This mode is entered when the application requests the FlexRay module to leave the disabled mode. If this
mode is entered, the protocol engine is in its
POC:default config state.
Depending on the values of the SCM, CHA, and CHB bits in the Module Configuration Register (MCR) ,
the corresponding FlexRay bus driver ports are enabled and driven.
The application can transition the protocol engine into other protocol states using the Protocol Operation
Control Register (POCR) . For details regarding protocol states, see FlexRay Communications System
Protocol Specification, Version 2.1 Rev A .