Usb-To-Uart Bridge - Xilinx AC701 User Manual

Refer to the Marvell 88E1116R Alaska Gigabit Ethernet transceiver data sheet for details
concerning the use of the Ethernet PHY user LEDs. They are referred to in the data sheet as
LED0, LED1, and LED2. The product brief and other product information for the Marvell
88E1116R Alaska Gigabit ethernet transceiver is available at
transceivers/alaska-gbe/.
The Marvell 88E1116R PHY data sheet can be obtained under NDA with Marvell

USB-to-UART Bridge

[Figure
The AC701 board contains a Silicon Labs CP2103GM USB-to-UART bridge device (U44)
which allows a connection to a host computer with a USB port. The USB cable is supplied
in the Evaluation Kit (standard-A plug to host computer, mini-B plug to AC701 board
connector J17). The CP2103GM is powered by the USB 5V provided by the host PC when
the USB cable is plugged into the USB port on the AC701 board.
Xilinx UART IP is expected to be implemented in the FPGA logic. The FPGA supports the
USB-to-UART bridge using four signal pins: Transmit (TX), Receive (RX), Request to Send
(RTS), and Clear to Send (CTS).
Silicon Labs provides royalty-free Virtual COM Port (VCP) drivers for the host computer.
These drivers permit the CP2103GM USB-to-UART bridge to appear as a COM port to
communications application software (for example, TeraTerm or HyperTerm) that runs on
the host computer. The VCP device drivers must be installed on the host PC prior to
establishing communications with the AC701 board.
Table 1-17
Table 1-17: USB J17 Mini-B Receptacle Pin Assignments and Signal Definitions
USB Receptacle Receptacle Pin
Pins (J17) Name
1 VBUS
2 D_N
3 D_P
4 GND
AC701 Evaluation Board
UG952 (v1.2) August 28, 2013
1-2, callout 16]
shows the USB signal definitions at J17.
Schematic
Net Name
USB_UART_ +5V from host system -
VBUS U12 CP2103 power
USB_D_N differential serial data
USB_D_P differential serial data
USB_UART_
GND
www.xilinx.com
U44 Pin
Description
(CP2103GM)
Bidirectional
(N-side)
Bidirectional
(P-side)
Signal ground
Feature Descriptions
www.marvell.com/
[Ref
U44 Pin Name
(CP2103GM)
7, 8 REGIN, VBUS
4 D-
3 D+
2, 29 GND, GND
3].
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