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Altera_Forum
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12 years ago

Using PLL "lock" signal as the async reset in Verilog

If I want to use the PLL "lock' signal to work as an async reset, the "lock" signal will keep low after the FPGA is powered and goes high after a duration. If I won't reset my PLL, then it means "loc...
Altera_Forum's avatar
Altera_Forum
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12 years ago

You do not want to use PLL lock as a reset signal directly. Not all PLL locked outputs have a debounce/deglitch filter, so they may toggle for a while before they stay in a static state.

Download the code associated with this PCIe test

http://www.alteraforum.com/forum/showthread.php?t=35678

There's a deglitch/debounce filter in there you can use to "clean-up" the locked signal. You can then decide whether to use the "clean" signal as a synchronous or asynchronous reset signal.

Cheers,

Dave