NXP Semiconductors freescale K51 Series Reference Manual

Table 43-94. State Descriptions for the Dual Role A Device Flow (continued)State Action ResponseA_WAIT_BCON After 200 msec without Attach or ID Interrupt. (This could waitforever if desired.)Go to A_WAIT_FALLTurn off DRV_VBUSA_VBUS_VLD Interrupt and B device attaches Go to A_HOSTTurn on Host ModeA_HOST Enumerate Device determine OTG Support.If A_VBUS_VLD/ Interrupt or A device is done and doesn't think hewants to do something soon or the B device disconnectsGo to A_WAIT_VFALLTurn off Host ModeTurn off DRV_VBUSIf the A device is finished with session or if the A device wants toallow the B device to take bus.Go to A_SUSPENDID Interrupt or the B device disconnects Go to A_WAIT_BCONA_SUSPEND If ID Interrupt, or if 150 msec B disconnect timeout (This timeoutvalue could be longer) or if A_VBUS_VLD\ InterruptGo to A_WAIT_VFALLTurn off DRV_VBUSIf HNP enabled, and B disconnects in 150 msec then B device isbecoming the host.Go to A_PERIPHERALTurn off Host ModeIf A wants to start another session Go to A_HOSTA_PERIPHERAL If ID Interrupt or if A_VBUS_VLD interrupt Go to A_WAIT_VFALLTurn off DRV_VBUS.If 3 –200 msec of Bus Idle Go to A_WAIT_BCONTurn on Host ModeA_WAIT_VFALL If ID Interrupt or (A_SESS_VLD/ & b_conn/) Go to A_IDLE43.7.2 OTG Dual Role B Device OperationA device is considered a B device if it connected to the bus with a USB Type B cable or aUSB Type Mini B cable.A dual role B device operates as the following flow diagram and state description tableillustrates.On-The-Go OperationK51 Sub-Family Reference Manual, Rev. 6, Nov 20111090 Freescale Semiconductor, Inc.