Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

NIOS II first time user

Hi

I am using NIOS II processor first time. Please help me with following questions.

Goal:

I am using signalTap to monitor output of my logic and my control values are being hard coded. I wanted to change my control signal in real-time and monitor the output of status signals.

In order to achieve my goal I am thinking about using NIOS II precessor.

0) Do I still need to write verilog code for cpu I/F ?

1) Since this an embedded system, I can define my register names and addresses in software?

2) after I create the NIOS II processor with on-chip memory using SOPC. what should I do next ...to connect my logic to NIOS II processor?

Thanks

Guru

10 Replies

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

    Have you ever used an embedded soft-core processor (ARM, MicroBlaze, Mico32, etc.) in an FPGA before?

    These page should become your new best friend:

    http://www.altera.com/literature/lit-nio2.jsp

    http://www.altera.com/support/ip/processors/nios2/ips-nios2_support.html

    What you really ought to do is run through some design tutorials first:

    http://www.altera.com/literature/hb/nios2/edh_ed_handbook.pdf

    http://www.altera.com/literature/tt/tt_nios2_hardware_tutorial.pdf

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

    Hi Jake,

    I went through some of the design examples. and understood how to create NIOS II processor using SOPC but still couldn't figure out how Nios II system can interact with other on-chip logic?

    If you can help me that would really helpful.

    Thanks.

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

    Here is one more tutorial for you. This will teach you how to create custom components for SoPC builder.

    http://www.altera.com/literature/hb/qts/qts_qii54007.pdf

    After that, if you still feel you need help, I would be glad to assist you.

    Basically there are two different methods to interfacing to custom logic:

    1 - Make your custom logic an SoPC builder component that resides inside your SoPC system. This is the most common approach and is what you'll learn in the above tutorial.

    2 - Export a portion of the avalon bus and connect it to your custom logic outside SoPC builder.

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

    Thank you Jake,

    Now , I understand about NIOS II Hardware Development.

    I have some questions on component editor.

    Under signals menu.

    name interface signal type width direction.

    In my design, I have some control signals and status signals. I am not sure what to option to select for interface and signal type for my signals.

    I read the Avalon Interface specification, page 14 onwards , It didn't help me much.

    Any suggestions.

    Thanks

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

    So are these signals that are not part of the avalon bus? In other words, are these signals that you are going to export out of the SoPC system and connect to other logic? If so, what you do is create a "conduit" interface. Then "export" for the signal type.

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

    Thanks Jake,

    For Now, I am not going to connect this signal to other logic. I am going to assign values to control signals and monitor the status signals( on Debug terminal) . Do I still need to use "conduit" and "export"?

    Thanks

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

    If you need access to the signals outside of your module (and outside of SoPC builder), then you must export them.

    You've got to assign all ports to some type of interface.

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

    Hi Jake,

    If I wanted use the clock directly from board to custom module. Do I have to select “clock_reset” or “conduit_end”. ?

    I have three clocks coming into custom block. If I am getting the following warning(in component editor), which means that ,I can only connect one clock externally and create other two clocks using PLLs (instantiate in my custom module)

    warning: clock_reset: signal clk appears 3 times (only once is allowed)

    I selected “conduit_end” for my control and status signals, which means that using NIOS II IDE, I am able to change the control values in real-time and read the status registers in real-time.

    Or Do I still need to connect the SignalTaps to monitor my status signals real-time?

    Thanks

    Guru