Copyright © 2003 Avnet, Inc. AVNET and the AV logo are registered trademarks of Avnet, Inc. All other trademarks are property of their respective owners.
Avnet Electronics Marketing
21 of 33
Rev 1.0 04/17/2006
Released
Literature # ADS-005104
2.10 LEDs
Eight discrete LEDs are installed on the board and can be used to display the status of the internal logic. These LEDs are attached as
shown below and are lit by forcing the associated FPGA I/O pin to a logic (1) and are off when the pin is either Low (0) or not driven.
LED #
Signal Name
FPGA pin#
D1 LED0
U4
D2 LED1
W4
D3 LED2
V6
D4 LED3
W7
D5 LED4
T8
D6 LED5
T7
D7 LED6
T6
D8 LED7
T5
Table 17 - LED FPGA Pin-out
2.11 Piezo Buzzer
The Spartan-3 Development board includes a piezo buzzer which may be used to generate simple audio tones. To enable the buzzer,
install a jumper at JP30 and JP20 (both installed by default). Drive the buzzer with an oscillating signal at pin AD25.
2.12 High-speed Serial Communication
2.12.1 LVDS
The Spartan-3 Development board uses one of the AvBus connectors (P2) to provide up to 30 LVDS pairs. These pairs, labeled
LVDS_P(0:29) and LVDS_N(0:29) are matched length. Each pair _P and _N are routed as differential pairs and are tightly coupled.
Each pair may be used as transmit or receive and should be configured accordingly using termination resistors at the provided surface-
mount pads. By default, no termination resistors are installed. A resistor should be added for each of the receive pairs (see schematic
sheet 14).
LVDS Signal
Net Length(mm)
Term Resistor
P2 Pin #
FPGA pin#
LVDS_P0 95.33915 R118 3 E24
LVDS_N0 95.26315
2 E23
LVDS_P1
95.02096
R119
74
F24
LVDS_N1
95.74285
73
F23
LVDS_P2 95.12807 R120 77 G23
LVDS_N2 95.84996
76 G22
LVDS_P3
95.6622
R121
9
E26
LVDS_N3
95.5862
8
E25
LVDS_P4 95.07538 R122 80 H21
LVDS_N4 95.79727
79 H20
LVDS_P5
95.16827
R123
83
J23
LVDS_N5
95.89016
82
J22
LVDS_P6 95.51224 R124 15 G21
LVDS_N6 95.43624
14 G20
LVDS_P7
95.13984
R125
86
K26
LVDS_N7
95.86173
85
K25
LVDS_P8 95.04799 R126 18 G26
LVDS_N8 95.61788
17 G25
LVDS_P9
95.17269
R127
21
H26
LVDS_N9
95.74258
20
H25
LVDS_P10 95.56244 R128 92 M22
LVDS_N10 95.63844
91 M12
LVDS_P11
95.1024
R129
24
K24
LVDS_N11
95.0264
23
K23
LVDS_P12 95.06954 R130 95 N22
LVDS_N12 95.80315
94 N21
LVDS_P13
95.71661
R131
27
L26
LVDS_N13
95.64061
26
L25
LVDS_P14 95.53837 R132 33 M20