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Altera_Forum
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17 years ago

My FPGA is not detecting the XOR edge..

I have this verilog code, which depends on either the posedge of the clock or the XOR of my data with its delayed version. assign x1 = data; assign x2 = ~x1; assign x3 = ~x2; assign XORData =...
Altera_Forum's avatar
Altera_Forum
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17 years ago

A Verilog assign surely causes no delay, it defines an alias signal in logic synthesis. It would require a /* synthesis keep = 1 */ attribute for the wire signals to physically synthesize logic cells. But you most likely need more than two logic cells to build a usable delay line.