SNIP_CLASSIC_FR_SECTION_7_4_POC_state_machine_control

7.4 POC state machine control [SWS_Fr_00477] ⌈Since a FlexRay CC is condition-based, it internally maintains a state machine, the Protocol Operation Control (POC) state machine. The state transitions are driven both by hardware related events as well as by commands passed by the host at the CHI (see [1] for details).⌋ [SWS_Fr_00478] ⌈The CHI commands driving the POC state machine are incorporated into several Fr module API functions. API functions affecting the POC state of a FlexRay CC are: • Fr_StartCommunication() • Fr_HaltCommunication() • Fr_AbortCommunication() • Fr_SendWUP() • Fr_ControllerInit() ⌋ [SWS_Fr_00438] ⌈All API functions other than those listed above shall not change the POC state of the FlexRay CC. Figure 3 shows the POC states of the FlexRay CC and the transitions applicable to the Fr module API functions. Note that • certain transitions (marked with *)) are performed by the invocation of a single API function call (Fr_ControllerInit()). • certain transitions might be implicitly performed by the FlexRay CC without external command invocation (dotted arrow) • certain transitions specified cannot be performed by the current Fr module API (not drawn in Figure 3 - compare to [5]). ⌋ Figure 7.2: FlexRay Driver POC State Machine Control