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Altera_Forum
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16 years ago

Stratix II GX Transceiver: Does 8b/10b coding work properly?

Hi again, I have limited the problem of undefined bits in the tx-output datastream to a problem with the 8b/10b-encoder. In ModelSim, I found the internal signal between the Phase Compensat...
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Altera_Forum
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16 years ago

Hi Daniel,

I have a question for you which is a bit off topic, but anyway.

I also have a Stratix II GX kit with an SFP module for optical transmission and would like to implement a loop-back test that you are implementing now.

The problem is that my SFP module uses NRZ encoding to transmit the data. I checked the SFP specification and actually it states that the modules can use 8b10, 4b5b, NRZ, Manchester or "Unspecified" coding. Since the SFP module is encoding the data i cannot use the 8b10b decoder in the ALTGX megafunction: i need to decode it using NRZ first and then apply a 8b10b decoder.

Have you come across this problem? Any idea how to solve it (besides building the PCS layer myself)?

Faruk