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Altera_Forum
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13 years ago

Signaltap II shows me incorrect time

Hi all I use both oscilloscope and signaltap II to observe an I2C waveform of 100k. The waveform is fine and I can see correct start/stop condition, address, and data. However, the period o...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

Hi Daixiwen

I'm using Cyclone IV dev. kit. So the 125MHz clock should be stable.

My design violates some of my timing constraints.

(It's weird that 125MHz clock has negative slack in holding time even though I've added "create_clock -name {clk125M} -period 8.000 -waveform { 0.000 4.000 } [get_ports {clk125M}])."

Does this negative slack cause me this problem?