Digilent 410-138P-KIT - Manual (Page 17)

Genesys Reference Manual
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Oscillators/Clocks
The Genesys board has several clock sources available, including a 3.3V 100MHz crystal oscillator, a
socket for a user-supplied half-size DIP oscillator, and two high-speed and highly stable differential
clock sources produced by an IDT 5V9885 programmable clock generator. The IDT clock generator is
programmed during manufacturing to produce several clocks required by the Genesys board,
including a 25MHz clock for the Ethernet PHY, a 24.576MHz clock for the Audio codec, a 12MHz
clock for the USB circuit, and two differential clocks (100MHz and 200MHz) for use by user circuits in
the FPGA.
OUT1
IDT5V9885
Clock Generator
25MHz
Crystal
Programming
header (SPI)
J12
25MHz
OUT2 24.576MHz
OUT3
200MHz
Ethernet Clock
Audio Clock
USB Clock
OUT4P
OUT4N
OUT5P
OUT5N
Virtex 5
H13
J14
H20
H19
100MHz
Oscillator
IC15
IC13
Oscillator
DIP socket
IC14
AG18
AH15
100MHz
12MHz
Differential
clock input
Differential
clock input