WARP v3 User Guide: USB UART

The WARP v3 board includes a USB UART transceiver to ease interaction with embedded processors running in the FPGA. The transceiver is the FTDI FT230X. For the full specs refer to the FT230X datasheet.

User designs must implement a UART in the FPGA to interface with the FT230X. Designs built in XPS can use the xps_uartlite pcore to implement STDIN/STDOUT for MicroBlaze designs. The FT230X supports all baud rates implemented by xps_uartlite. Ensure your terminal emulator configures the virtual COM port for the same baud rate specified in the xps_uartlite instance.

The USB UART transceiver is connected to two FPGA pins, listed in the UCF snippet below.

Net fpga_0_UART_USB_TX_pin LOC = H9 | IOSTANDARD=LVCMOS25; #FT230X RXD pin
Net fpga_0_UART_USB_RX_pin LOC = J9 | IOSTANDARD=LVCMOS25; #FT230X TXD pin

Using the UART on a PC

Accessing the USB UART interface from a PC requires installation of the FTDI Virtual COM Port (VCP) driver. This driver is maintained by FTDI and is available free on their web site. We have successfully tested the USB UART using the FTDI drivers under Windows 7 and OS X. Any platform supported by FTDI should also work.

Once the drivers are installed your PC will recognize a new COM port when you connect a micro USB cable to the WARP v3 board. Refer to the USB UART howto for instructions on managing the COM port and recommendations on terminal emulators.

Last modified 12 years ago Last modified on Aug 31, 2012, 11:49:01 PM