Terasic Altera DE3, User Manual

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DE3 User Manual
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Figure 2.18. Connections between the SD card and Stratix III
2.11 LED Indicators
The DE3 board includes some LEDs to indicate the specified hardware status. The relationship of
LED names and their associated functions are list in Table 2-5 .
Table 2-5 Description for LED indicator
LED Name Descriptions
POWER Light on when Power switch(SW5) is turned on
CONF_DONE
Light on when the configuration data is received by Stratix
III FPGA without error ad initialization cycle starts.
LOAD Light on when USB blaster circuit transmits or receives data
LINKA
Light on when HSTC connector A top (J1) is connected with
an extended board
LINKB
Light on when HSTC connector B top (J3) is connected with
an extended board
LINKC
Light on when HSTC connector C top (J5) is connected with
an extended board
LINKD
Light on when HSTC connector D top (J7) is connected with
an extended board
OVT
Light on when the temperature value of the FPGA is higher
than the threshold value setting in the temperature sensor.
USB3,
USB2,
USB1
Power LED indicators for USB port3 (J17), port2 (J16), and
port1 (J1). Each LED will be on as soon as the port power of
the respective port is enabled by software, for example,
after loading drivers
2.12 Clock Circuitry
Clock inputs:
The clock input source of Stratix III FPGA comes from the clock buffer, HSTC connectors, GPIO
expansion headers, and SMA connector as indicated in Figure 2.19 . Three of five clock inputs are
connected to the dedicated high speed clock input pins of the FPGA, which allows users to use any
of these clocks as a source clock for the PLL circuit.
Note: The 3 clock inputs connected to the dedicated inputs of the FPGA are (CLKIN_2, CLKIN_n1,
and CLKIN_p1 respectively).
Clock outputs: