Interfaces; Usb Interface - Altera Cyclone III FPGA Reference Manual

Interfaces

Interfaces
2–8
Cyclone III FPGA Starter Board
Table 2–5. Board Jumpers (Part 2 of 2)
Jumper Board
Reference
JP5 3.3 V supply for the MAX device and HSMC. To supply an
external voltage, remove the jumper and connect the external
supply to pin 2. (Pin 2 has a rounded shape on the bottom of the
board.)
JP6 Sense resistor for measuring the power consumed by the 1.2 V
V supply to the Cyclone III device.
CCINT
JP7 1.8 V power supply to flash device. To supply an external
voltage, remove the jumper and connect the external supply to
pin 2. (Pin 2 has a rounded shape on the bottom of the board.)
JP8 Adding the shunt enables configuration of the Cyclone III device
using the JTAG header and an external USB-Blaster. When the
shunt is not in place, the embedded USB-Blaster circuitry must
be used to configure the Cyclone III device. (The board ships
without the JTAG header populated.)
This section describes the following Cyclone III FPGA starter board's
interface blocks:
■

USB interface

■
HSMC expansion connector
■
General user interfaces
USB Interface
The USB-Blaster circuitry is built onto the board. You can simply plug the
USB cable (provided with the kit) into USB connector J3 on the board and
the other end to a USB port on your computer to program and
communicate with the Cyclone III device via the JTAG port.
A USB physical connection is used to enable computers to communicate
with the starter board. To simplify the USB interface, the board contains a
FTDI FT2232L USB universal asynchronous receiver/transmitter (UART)
circuit. The data from the FTDI chip is translated into a JTAG stream
using the Altera EPM3128A CPLD connected to the Cyclone III device's
dedicated JTAG port.
The 5 V supply for the FTDI device is drawn from the USB connection.
The rest of the circuit operates on 3.3 V supply with 100 mA maximum
and 1.8 V supply with 900 mA maximum voltage.
Reference Manual
Jumper Operational Descriptions
Altera Corporation
October 2007