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Altera_Forum's avatar
Altera_Forum
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15 years ago

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

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.

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    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.
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

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

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    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
  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    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.