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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

Thank you for your help.

I attach two images.

One shows the waveform captured by an oscilloscope.

(Waveform in yellow color is sda; waveform in blue color is scl)

The other shows the waveform captured in signaltap ii.

The period of scl in oscilloscope is about 12~13 us.

However, the period of scl in signaltap ii is about 1~2 us.

The time unit I set in signaltap ii is 1 ns.