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Altera_Forum's avatar
Altera_Forum
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14 years ago

Virtual JTAG: "Hub IP" register value?

Hello.

According to the virtual JTAG Megafunction guide the "Hub IP configuration register" contains the following values:

Bits 7-0: SUM(m,n)

Bits 18-8: ALTERA_MFG_ID = 0×6E

Bits 26-19: N

Bits 31-27: version

However in my tests (using Quartus II 11.0 and the Cyclone II evaluation board) Bits 7-0 seem to contain the number "m" only, not "m+n".

In the current project the virtual IR register (User1) is 13 bytes long (n=3, m=10) and bits 7-0 of the configuration register contain the number 10, not 13 as expected. I also tried (n=1, m=4) and (n=1, m=5); the configuration register values were 4 and 5, not 5 and 6 as expected.

Is this

- A bug in the virtual JTAG Hub or

- a bug in the documentation or

- do I do anything wrong??

Thanks.

Martin

5 Replies

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

    Hey Dave,

    I have been struggling issuing the VIR HUB_INFO instruction and then shifting out the resulting data. How to target the SLD_hub in that case?

    Thanks.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    --- Quote Start ---

    I have been struggling issuing the VIR HUB_INFO instruction and then shifting out the resulting data. How to target the SLD_hub in that case?

    --- Quote End ---

    Download the zip file for this tutorial:

    http://www.alterawiki.com/wiki/using_the_usb-blaster_as_an_sopc/qsys_avalon-mm_master_tutorial

    There's a Tcl script in there for use with Quartus stp. It has all the hub interrogation code, eg., print_hub_info and print_node_info. Read that code, it'll show you how it all works.

    Cheers,

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

    Hats off to you Sir, That bit of information was what I was missing in my logic

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

    --- Quote Start ---

    Hats off to you Sir, That bit of information was what I was missing in my logic

    --- Quote End ---

    You're welcome!

    Cheers,

    Dave