Digilent Nexys 3 Reference Manual page 2

Nexys 3™ FPGA Board Reference Manual
23
Adept USB2
Config & data
Cellular RAM
16MByte
47
Spartan-6
Parallel PCM
Nonvolatile
Memory
16MByte
XC6SLX16
CSG324C
SPI PCM (x4)
8
Nonvolatile
Memory
16MByte
28
10/100
Ethernet PHY
10
8-bit VGA
1 Configuration
After power-on, the Spartan-6 FPGA board must be configured (or programmed) before it can perform any
functions. The FPGA can be configured in one of four ways: a PC can use the Adept "USB Prog" port to program
the FPGA any time power is on; a configuration file stored in the non-volatile parallel PCM device can be
transferred to the FPGA at power-on using the BPI-UP port; a file stored in the non-volatile serial (SPI) PCM device
can be transferred to the FPGA using the SPI port; or a programming file can be transferred from a USB memory
stick attached to the USB HID port. An on-board "mode" jumper (J8) selects between the programming modes as
shown in the J8 Mode legend in the figure below. JTAG Mode can be accessed at any time without changing
jumpers.
Adept "USB Prog" Port
Micro-AB USB
Connector
6-pin JTAG
Header (J7)
Host Port
Type A USB
Connector
Programming files are stored in SRAM-based memory cells within the FPGA. This data defines the FPGA's logic
functions and circuit connections, and it remains valid until it is erased by removing board power, by pressing the
reset button attached to the PROG input, or by writing a new configuration file using the JTAG port.
FPGA configuration files transferred via the JTAG port use the .bin or .svf file types, files transferred from a USB
stick use the .bit file type, and BPI or SPI programming files can use .bit, .bin, or .mcs types. The ISE/WebPack or
EDK software from Xilinx can create bit, svf, bin, or mcs files from VHDL, Verilog, or schematic-based source files
Copyright Digilent, Inc. All rights reserved.
Other product and company names mentioned may be trademarks of their respective owners.
4
USB HID Host
Mouse/Keyboard
2
USB-UART
Clock 100MHz
22
Basic I/O
LEDs, Btns, Swts
40
High-Speed
Expansion
32
Pmod Port
Expansion
USB
Controller
JTAG
Port
1x6 JTAG
Header
2
Serial
PIC24
Prog. Port
Spartan-6 LX16 features include:

2,278 slices each containing four 6-input LUTs
and eight flip-flops

576Kbits of fast block RAM

two clock tiles (four DCMs & two PLLs)

32 DSP slices

500MHz+ clock speeds
Micron SPI Quad
SPI
mode PCM (P5Q)
Port
Micron Parallel
BPI
PCM (P8P)
Port
J8
M0
M1
Spartan6
Done
Prog
M0 M1
BPI UP
SPI
SLV Serial
Programming
Mode
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