Enhanced Queued Analog-to-Digital Converter (eQADC)MPC5566 Microcontroller Reference Manual, Rev. 219-72 Freescale Semiconductor19.4.3.6 CFIFO and Trigger Status19.4.3.6.1 CFIFO Operation StatusEach CFIFO has its own CFIFO status field. CFIFO status (CFS) can be read from EQADC_CFSSR (referto Section 19.3.2.11, “eQADC CFIFO Status Register (EQADC_CFSR).” Figure 19-39 and Table 19-45indicate the CFIFO status switching condition. Refer to Table 19-18 for the meaning of each CFIFOoperation status. The last CFIFO to transfer a command to an on-chip ADC can be read from the LCFTn(n=0,1) fields (see Section 19.3.2.10, “eQADC CFIFO Status Snapshot Registers 0–2(EQADC_CFSSRn).” The last CFIFO to transfer a command to a specific external command buffer canbe identified by reading the EQADC_CFSSRn[LCFTSSI] and EQADC_CFSSRn[ENI] fields (seeSection 19.3.2.10, “eQADC CFIFO Status Snapshot Registers 0–2 (EQADC_CFSSRn).”ContinuousScan EdgeNo A corresponding edgeoccurs.Yes Yes None.ContinuousScan LevelNo Gate is opened. No No The eQADC also stops transfersfrom the CFIFO when CFIFOstatus changes from triggereddue to the detection of a closedgate. 51 Refer to Section 19.4.3.6.2, “Command Queue Completion Status,” for more information on EOQ.2 Refer to Section 19.4.3.6.3, “Pause Status,” for more information on pause.3 The eQADC always stops command transfers from a CFIFO when the CFIFO operation mode is disabled.4 The eQADC always stops command transfers from a CFIFO when a higher priority CFIFO is triggered. Refer toSection 19.4.3.2, “CFIFO Prioritization and Command Transfer,” for information on CFIFO priority.5 If a closed gate is detected while no command transfers are taking place, it has an immediate effect on the CFIFOstatus. If a closed gate is detected during the serial transmission of a command to the external device, it has no effecton the CFIFO status until the transmission completes.Table 19-44. CFIFO Scan Trigger Mode—Command Transfer Start/Stop SummaryTrigger ModeRequiresAsserted SSSto RecognizeTriggerEvents?Command TransferStart/Restart ConditionStop onassertedEOQbit 1?Stop onassertedPausebit 2 ?Other Command Transfer StopCondition3 4
