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Is it possible to detect both K28.5+ and K28.5- symbols with ALTGX in Basic mode

Altera_Forum
Honored Contributor II
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Hello. 

 

I am designing SATA core for Cyclone IV GX device, using its ALTGX transceivers. 

There is not enough information about it, I think. 

I have read C4-GX datasheet, quartus-help about ALTGX and other info. And I did not understand, is it possible to detect both patterns simultaneously. 

There is only 1 document says? that it is possible, this is - quartushelp.altera.com section about ALTGX megafunction. 

This feature is absent in MegaWizard, and in Cyclone 4 datasheet. 

 

The QuartusHelp says, that it is regulated by parameter RX_ENABLE_TRUE_COMPEMENT_MATCH_IN_WORD_ALIGN. But, again, this parameter is not adverted in Cyclone datasheet "Transceivers" chapter and in MegaWizard.
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Altera_Forum
Honored Contributor II
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Hello, 

 

I have checked this out in RTL simulation, it works on both K28.5+ and K28.5-, even though you can only specify one of the two in the MegaWizard.
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Altera_Forum
Honored Contributor II
286 Views

Thanks. I asked the same question to Altera Support. It is interesting, what they answer..

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Altera_Forum
Honored Contributor II
286 Views

Hi 

 

I use the Cyclone IV GX with a fibre optic link, and the other end is a Cypress Hotlink serdes. 

 

I guess you are going to use the K28.5+ - to sync the link? This works fine for me. You will get the control code out of the receiver with the hex value on the data lines (0xBC) and the rx_ctrldetect signal high. There is also an optional running disparity which will tell you which one (+ or -) was detected. 

 

Hope that helps. 

 

DaveLuscher
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Altera_Forum
Honored Contributor II
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Thanks to all. Altera answered. 

They say, that Cyclone IV GX transceiver detects pattern and it's complement concurrently, and they will add this to handbook later.
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