USBx_ENDPTn field descriptions (continued)Field Descriptioncauses the USB Module to return a STALL handshake. After an endpoint is stalled it requires interventionfrom the Host Controller.0EPHSHKWhen set this bit enables an endpoint to perform handshaking during a transaction to this endpoint. Thisbit is generally 1 unless the endpoint is Isochronous.33.5.18 USB Control register (USBx_USBCTRL)Address: 4007_2000h base + 100h offset = 4007_2100hBit 7 6 5 4 3 2 1 0Read SUSP PDE 0WriteReset 1 1 0 0 0 0 0 0USBx_USBCTRL field descriptionsField Description7SUSPPlaces the USB transceiver into the suspend state.0 USB transceiver is not in suspend state.1 USB transceiver is in suspend state.6PDEEnables the weak pulldowns on the USB transceiver.0 Weak pulldowns are disabled on D+ and D–.1 Weak pulldowns are enabled on D+ and D–.Reserved This field is reserved.This read-only field is reserved and always has the value 0.33.5.19 USB OTG Observe register (USBx_OBSERVE)Provides visibility on the state of the pull-ups and pull-downs at the transceiver. Usefulwhen interfacing to an external OTG control module via a serial interface.Address: 4007_2000h base + 104h offset = 4007_2104hBit 7 6 5 4 3 2 1 0Read DPPU DPPD 0 DMPD 0 0WriteReset 0 1 0 1 0 0 0 0Chapter 33 Universal Serial Bus (USB) FS SubsystemKL27 Sub-Family Reference Manual , Rev. 5, 01/2016Freescale Semiconductor, Inc. 555
