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Figure 2–21 – Altera Nios Development Board Cyclone II Edition User Manual

Page 54

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2–42

Reference Manual

Altera Corporation

Nios Development Board Cyclone II Edition

May 2007

Board Components

Figure 2–21. Clock Circuitry

Note to

Figure 2–21

:

(1)

To use an external clock signal, remove the crystal oscillator from its socket. Make
sure to note the correct orientation of the oscillator before removing it.

osc_CLK0

osc_CLK1

sram_CLKIN

sdram_CLKIN

MAX (U3)

cpld_CLKOSC

sdram_CLK_p

sdram_CLK_n DDR SDRAM (U63)

SSRAM (U74)

sram_CLK

PMC_CLK

PMC (JH1 & JH2)

FPGA

(U62)
PLLs

PROTO1

proto1_PLLCLK

proto1_CLKOUT

proto1_OSCCLK

Mictor (J25)

mictor_CLK

PROTO2

proto2_PLLCLK

proto2_CLKOUT

proto2_OSCCLK

SMA External

Input (J4)

Oscillator (Y2)

Clock

Buffer

(U2)