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

Altera_Forum
Honored Contributor II
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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!!!
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Altera_Forum
Honored Contributor II
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whatever the input the ouput is k28.5 wrong input ? wrong data rate? wrong clk ? wrong mode?

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Altera_Forum
Honored Contributor II
298 Views

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?

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Altera_Forum
Honored Contributor II
298 Views

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
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Altera_Forum
Honored Contributor II
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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.

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Altera_Forum
Honored Contributor II
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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??
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Altera_Forum
Honored Contributor II
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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. .
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