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Altera_Forum
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15 years ago

PCIe ALTGX reconfig_clk frequency?

The documentation for the stratix IV is somewhat confusing on this matter. It says: "Offset cancellation logic requires a separate clock. In PCIe mode, you must connect the clock input to the...
Altera_Forum's avatar
Altera_Forum
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15 years ago

While waiting for a better answer, here is my experience. I have not used the PCIe mode, but did use other modes that require the reconfig_clk. the reconfig_clk must be between 37.5 and 50 MHz. The doc also says that the reconfig_clk must come from an input pin. However, there is an app note (forgot which) that shows you how to use a pll for that - in case you do not have a separate 37.5 to 50 MHz clock coming in.

Knowing what the reconfig block does, I don't think they would require the reconfig_clk to be different for PCIe.

Here is the link to using a pll for reconfig_clk: http://www.altera.com/support/kdb/solutions/rd12172009_309.html