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Word alignment pattern

vkc
Beginner
265 Views
Hii ,I am designing sfpdp reciever.I am using stratix 4 fpga for the same with data width 32. what is the word alignment pattern to be used.I dont have any details regarding word alignment pattern used on the transmitter side.

I tried with standard word alignment pattern BCBCBCBC and BC1CBC1C. It didnt work.can anyone help me with this.
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9 Replies
SengKok_L_Intel
Moderator
250 Views

Hi,


You may refer to the following page 59 for the Word Aligner in detail. You may either use manual, bitslipping, or built-in synchronization mode.

https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/hb/stratix-iv/stx4_siv52001...


Regards -SK



vkc
Beginner
232 Views
According to my understanding those modes work when we know the predefined word alignment pattern to be recieved. In my case I dont know the word alignment pattern.





vkc
Beginner
230 Views
Transmitter sends some control code before actual data transmission begins. So we may need to use it as word alignment pattern on the reciever side for synchronization. So I tried with standard control code k28.5 as word alignment pattern but it didnt work.

So is there a method to find the control code.
SengKok_L_Intel
Moderator
228 Views

Hi,


The word alignment pattern has to predefined in the ALTGX Megawiard, each of the protocols should have a predefined alignment pattern. You may ensure the alignment is successful first, and then create some custom logic to detect difference control code if needed.





vkc
Beginner
227 Views
Can you please tell us the predefined word alignment pattern for sfpdp protocol to be used.
SengKok_L_Intel
Moderator
225 Views

Hi,

I don't have the detail of this protocol. You may perform a simple loopback test (TX -> RX) to ensure if the word alignment pattern is successfully aligned if you are sending a known control code from TX. This can help to rules out any user error.


vkc
Beginner
219 Views
Hii ,I did not get any information regarding the word alignment pattern in specifications. transmitter side is an ip core designed by some other company. We have access to only .sof file. We are getting some random incorrect data.

We are struck in our project please help us with this.
SengKok_L_Intel
Moderator
217 Views

I would suggest you start with a simple design with the loopback test (TX -> RX) to ensure the word aligner is working first, this is to rule out any receiver related problem. You might need to contact the third party who design the transmitter for the detail as well.




SengKok_L_Intel
Moderator
190 Views

If further support is needed in this thread, please post a response within 15 days. After 15 days, this thread will be transitioned to community support. The community users will be able to help you with your follow-up questions.


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