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Altera_Forum's avatar
Altera_Forum
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15 years ago

Osc. input to Cyclone

Hi there,

Currently taking a design from development board to a custom PCB. When designing the schedule for the PCB I got stuck on how to connect my 50 MHz oscillator to the Cyclone IV device. It has about 15 clock inputs, are all of them required to be connected or is one enough if I am only using the clock to a Nios processor?

Thanks in advance,

mr_embedded

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    15 years ago

    No you only need to connect it to one input, fortunately! It will be either fed to a pll or routed as a global clock and can be used everywhere inside the fpga. Each clock input pin can be connected to a different clock.

    Before you finish the PCB (or even better, before you start routing it) it can be a good idea to make a basic FPGA project with all your pins correctly assigned and run a I/O check from the Quartus pin assignment editor. Just to check you got all the pins right.