Modem User Manual

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5.11.5 USB
Pin Name Direction Function
45 USBDP In/Out USB data positive
46 USBDN In/Out USB data negative
49 VUSB Input USB DC power
The USB interface is compliant with the USB2.0 standard for a full speed (12Mbps)
endpoint device. Together with VUSB and GND it creates a standard USB 4-pin
interface. VUSB (VBUS in the USB standard) is nominally 5.0V.
USB is not available on legacy variant GR64 devices (DPY 102 1494/10
& DPY 102 1494/30 products). On these products, the signal
connections can be left un-terminated.
The USB interface has the following features:
• Full-speed (12 Mbits/s) device operation
• 16 unidirectional endpoints
• Each endpoint capable of supporting control, interrupt, isochronous and bulk
transfer
• Programmable endpoint types and FIFO sizes and internal 1120-byte logical
(2240-byte physical for dual-packet mode) shared FIFO storage allow a wide
variety of configurations.
• Dual-packet mode of FIFOs reduces latency
• USB reset can be programmed to clear device address.
• Firmware ability to wake up and reset a suspended device
• 8, 16, 32, and 64-byte FIFO sizes for non-isochronous transfers
• 64, 256, 512, and 1024-byte FIFO sizes for isochronous transfers
• Firmware downloading
• Trace debug port for module diagnostics
The USB interface supports 3GPP TS 27.010 multiplexing, and may be used as the
primary AT-command interface.
Internally, the USBDP line is pulled up by a 1.5K resistor, in accordance with the USB
standard, to indicate that it’s a full-speed capable device to the USB controller.
To implement successful applications using the GR64 USB interface, users should
familiarize themselves with the USB specification.
NOTE