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Altera_Forum's avatar
Altera_Forum
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15 years ago

Test benching LVDS ports

I have a Verilog design that I'm simulating with a Verilog test bench using Altera-ModelSim. The desgin has LVDS ports and when the simulation is run ModelSim complains about unconnected xxx(n) ports, the negative LVDS inputs. How do I specify the driving of these ports from the test bench when the Verilog design doesn't have explicit ports for the negative LVDS pins?

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    you must be doing a gate level simulation? you may have to drive the -n legs from your test bench

  • Altera_Forum's avatar
    Altera_Forum
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    Yes this is a gate level sim. How do I drive the (n) pins from the Verilog test bench? Or, how do I explicitly define the (n) pins in the device Verilog file? I just left the (n) pins undefined and Quartus automatically assigned them, so there is no definition for these pins in the Verilog design file. Is there a way to explicitly define the (n) pins in the design file?