Sigma manual Using the DE2-70 Board, Configuring the Cyclone II FPGA, Chapter

DE2-70 User Manual

Chapter 5

Using the DE2-70 Board

This chapter gives instructions for using the DE2-70 board and describes each of its I/O devices.

5.1 Configuring the Cyclone II FPGA

The procedure for downloading a circuit from a host computer to the DE2-70 board is described in the tutorial Quartus II Introduction. This tutorial is found in the DE2_70_tutorials folder on the DE2-70 System CD-ROM. The user is encouraged to read the tutorial first, and to treat the information below as a short reference.

The DE2-70 board contains a serial EEPROM chip that stores configuration data for the Cyclone II FPGA. This configuration data is automatically loaded from the EEPROM chip into the FPGA each time power is applied to the board. Using the Quartus II software, it is possible to reprogram the FPGA at any time, and it is also possible to change the non-volatile data that is stored in the serial EEPROM chip. Both types of programming methods are described below.

1.JTAG programming: In this method of programming, named after the IEEE standards Joint Test Action Group, the configuration bit stream is downloaded directly into the Cyclone II FPGA. The FPGA will retain this configuration as long as power is applied to the board; the configuration is lost when the power is turned off.

2.AS programming: In this method, called Active Serial programming, the configuration bit stream is downloaded into the Altera EPCS16 serial EEPROM chip. It provides non-volatile storage of the bit stream, so that the information is retained even when the power supply to the DE2-70 board is turned off. When the board's power is turned on, the configuration data in the EPCS16 device is automatically loaded into the Cyclone II FPGA.

The sections below describe the steps used to perform both JTAG and AS programming. For both methods the DE2-70 board is connected to a host computer via a USB cable. Using this connection, the board will be identified by the host computer as an Altera USB Blaster device. The process for installing on the host computer the necessary software device driver that communicates with the USB Blaster is described in the tutorial Getting Started with Altera's DE2-70 Board. This tutorial is available on the DE2-70 System CD-ROM.

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