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Altera_Forum's avatar
Altera_Forum
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12 years ago

Is there any document describing Altera Jtag components?

I find the component **_jtag in the library of Quartus, but cann't find detailed information about it.

The component is as below:

component cyclone_jtag

generic (

lpm_hint : string := "UNUSED";

lpm_type : string := "cyclone_jtag" );

port(

clkdruser : out std_logic;

ntrst : in std_logic := '0';

runidleuser : out std_logic;

shiftuser : out std_logic;

tck : in std_logic := '0';

tckutap : out std_logic;

tdi : in std_logic := '0';

tdiutap : out std_logic;

tdo : out std_logic;

tdouser : in std_logic := '0';

tdoutap : in std_logic := '0';

tms : in std_logic := '0';

tmsutap : out std_logic;

updateuser : out std_logic;

usr1user : out std_logic

);

end component;

7 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    12 years ago

    Hi, Dave,

    I am trying to use these family_jtags to connect our JTAG-supported soft modules(inside FPGAs), so we can access both vendor's JTAG component and our soft modules by software.

    Your notes give the information about virtual jtag, but the component "family_jtag" is the primitive. What I really want to use is the primitive.

    Is there any detailed information about this component's pinout?
  • Altera_Forum's avatar
    Altera_Forum
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    12 years ago

    --- Quote Start ---

    I am trying to use these family_jtags to connect our JTAG-supported soft modules(inside FPGAs), so we can access both vendor's JTAG component and our soft modules by software.

    Your notes give the information about virtual jtag, but the component "family_jtag" is the primitive. What I really want to use is the primitive.

    Is there any detailed information about this component's pinout?

    --- Quote End ---

    The *only* supported JTAG component is the SLD_Virtual_JTAG component. Altera's JTAG-to-Avalon components are internally constructed from a component that is essentially identical to this part too, eg., see these notes:

    http://www.ovro.caltech.edu/~dwh/correlator/pdf/altera_jtag_to_avalon_analysis.pdf

    I'm still not quite clear on your requirements:

    1) If you have a JTAG-like component that you want to access, you need to connect it via the SLD_Virtual_JTAG component.

    2) If you have a component with registers, then you can access it via a JTAG-to-Avalon-MM bridge, just provide your component with an Avalon-MM slave interface.

    Can you please clarify.

    Cheers,

    Dave
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    My application is the first one.

    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?

    Regards,

    Ryan
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    --- Quote Start ---

    My application is the first one.

    --- Quote End ---

    Then Altera will only support you if you use the SLD_Virtual_JTAG component.

    --- Quote Start ---

    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?

    --- Quote End ---

    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
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    --- Quote Start ---

    Thanks for your advice.

    --- Quote End ---

    No problem. Hopefully it saved you some time.

    If you have a specific use-case that you do not want to discuss here, eg., a code example, just send me an email directly (to my forum name).

    Cheers,

    Dave