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

Altera_Forum
Honored Contributor II
850 Views

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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6 Replies
Altera_Forum
Honored Contributor II
103 Views

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

Altera_Forum
Honored Contributor II
103 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?

Altera_Forum
Honored Contributor II
103 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
Altera_Forum
Honored Contributor II
103 Views

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
Honored Contributor II
103 Views

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
Honored Contributor II
103 Views

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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