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My application is the first one.
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Then Altera will only support you if you use the SLD_Virtual_JTAG component.
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Did you mean users can not use "cyclone_jtag" component in the "..\quartus\libraries\vhdl\cyclone_components.vhd"?
What's this "cyclone_jtag" component for?
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It might be used when creating a simulation model.
You might also find that if you use a MegaWizard to instantiate a JTAG component that this component is internally used. However, direct instantiation of the SLD_Virtual_JTAG should give you identical (or at least very similar) control.
Keep in mind that any VHDL you can read in the atoms files or the low-level device files *is not real*, i.e., you will never get to see what Altera synthesis files look like. That is all part of their secret-sauce.
If you are trying to create a vendor-neutral interface to your JTAG components, then you need to go through the SLD_Vitual_JTAG components for Altera, and the BSCAN components for Xilinx, and I forget what the JTAG components are called for Lattice. Bottom line is you have to use a vendor specific component to access your vendor neutral code.
Cheers,
Dave
Honored Contributor
