Altera Cyclone II DSP Development Board - Manual (Page 70)

2–62 Reference Manual Altera Corporation
Cyclone II DSP Development Board August 2006
Clock Circuitry
Clock Select Jumper (J19)
J19 determines which input to U16 (the selected clock oscillator or the
SMA clock will be used to determine the clock outputs of U16. See
Figure 2–22 and Figure 2–23 .
Socket for a Custom Clock Oscillator (J20)
J20 is a socket for connecting a half-can oscillator that can be used instead
of the on-board clock oscillator (U20). An oscillator inserted into J20 is
called the custom clock and is not included in the DSP Development Kit,
Cyclone II Edition. The custom oscillator can be selected to be the input to
U16.The J20 socket is mounted on top of U20, the on-board clock
oscillator, as shown in
Figure 2–22 .
D/A Converter CLK SMA Connector (J26)
J26 is an SMA connector that provides an external clock input to the D/A
converter. It can be selected to be the D/A converter clock. See
“D/A
Converter Clocks” on page 2–18 . J26 is shown in Figure 2–7 on page 2–18 .
Table 2–12 on page 2–19 describes the D/A converter clock source
settings.
A/D Converter CLK SMA Connector (J27)
J27 is an SMA connector that provides an external clock input to the A/D
converter. It can be selected to be the A/D clock. See
“A/D Converter
Clocks” on page 2–23 . J27 is shown in Figure 2–10 on page 2–23 .
Table 2–17 on page 2–24 describes the A/D converter clock source
settings.
D/A Converter CLK Select Jumper (J35 & J34)
J35 is used to choose between three clocking inputs to select the
DAC CHANNEL A clock. J34 is used to choose between three clocking
inputs to select the DAC CHANNEL B clock. The J35 and J34 D/A
converter clock select settings are described in
Table 2–12 on page 2–19 .
J35 and J34 are shown in Figure 2–7 on page 2–18 .
A/D Converter CLK Select Jumper (J37 & J36)
J37 is used to choose between three clocking inputs to select the
ADC CHANNEL A clock. J36 is used to choose between three clocking
inputs to select the ADC CHANNEL B clock.The J37and J36 A/D
converter clock select settings are described in
Table 2–17 on page 2–24 .
J37 and H36 are shown in Figure 2–10 on page 2–23 .