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Altera_Forum
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10 years ago

modelsim10.1c cycloneiv altgx simulation the output is always be K28.5 HELP!!

I'm a greenhand in simulation , sinx everyone who may give me a hand in advance!

I simulate the ALTGX ip with modelsim 10.1c but when i am sending the 8b/10b sequence (K28.5 D21.4 D21.5 D21.5), the output is always K28.5+ then K28.5-

i don't know why .

the mode i choose is basic mode ,the ALTGX signal picture and simulate pictures are as follows , can any professer tell what i was wrong

In the picture I connect the tx_dataout to rx_datain so the two wave is the same , and all the input signal is included in the picture , why i always get

the K28.5

THANKS again for the attention!!!

6 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    10 years ago

    whatever the input the ouput is k28.5 wrong input ? wrong data rate? wrong clk ? wrong mode?

  • Altera_Forum's avatar
    Altera_Forum
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    10 years ago

    Do you mean that no matter what data input the output is always K28.5? Have you try with other Modelsim and Quartus II version?

  • Altera_Forum's avatar
    Altera_Forum
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    10 years ago

    thx for answering

    yes whatever input is the output is the same k28.5+ after k28.5-

    I havn't change version yet !

    I do some other test ,

    I try to change the ALTGX mode to strarixiv of no use

    I try to change the clk frequency of no use

    I try to use the modelsim "create wave" to generate the clk signal instead of the vhdl then the simulation can't work with

    "Fatal error in Process line__168 at K:/altera/15.0/quartus/eda/sim_lib/stratixiv_hssi_atoms.vhd line 172 "

    but what matters me most is when I download my design to the cyloneiv , it works , I can't believe it , that's good but that's not what I want!

    maybe I should change my modelsim version

    sinx
  • Altera_Forum's avatar
    Altera_Forum
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    10 years ago

    Seems like simulation does not work but hardware work. apart from trying different version, you might want to cross check the test bench to see.

  • Altera_Forum's avatar
    Altera_Forum
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    10 years ago

    Is there something I should pay special attention to in testbench about ALTGX,

    the wave is up there , finding something wrong is beyond my ability now , can you give me some suggest??
  • Altera_Forum's avatar
    Altera_Forum
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    10 years ago

    I find out the problems is come frome pcs part , the output of the pcs is K28.5 whatever input is ,I change THE ALTGX to transimitter only model , only 3 port ---- clk datain and control bit

    ,even in this simple MODE the pcs output is wrong. .