Forum Discussion

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

RedBoot with Non-PC CPU

Hi,

I work on a project where a Software loading is needed for the Nios.

The RedBoot was considered, but the host computer (which delivers the above software to be loaded on the Nios) is not a PC, but rather a POWERPC on another board.

As you all know, RedBoot needs a terminal with a skilled user on one side (the host side) - something we can't afford in this case: we need an automatic procedure with a specific protocol between the 2 processors to do the job.

Has anybody here done something like this before? Is it possible? Is RedBoot the answer to our needs?

Thank you for reading...thank you very much for answering http://forum.niosforum.com/work2/style_emoticons/<#EMO_DIR#>/biggrin.gif

3 Replies

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

    It is actually possible to get redboot to boot an application without human intervention. The commands you would have typed at the console can be "scripted" in the redboot config data so that it will automatically download and boot an application. More detail on this can be found in the redboot manual (which comes with the eCos documentation).

    However using Redboot in this case sounds like using a slegehammer to crack a nut. It sounds like you need to write yourself a simple monitor program which will sit in a loop waiting for a PIO to assert (or equivalent), and then jumps to the entry point for your application.

    The PowerPC can then load the code and signal the Nios to start using the PIO.

    I&#39;d recommend that you write your monitor program as a HAL application using the alt_main() entry point.

    This is more of a "push" rather than a "pull" model, which may or may not be apropriate depending on your system.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    21 years ago

    Hi again,

    First of all, thank you very much for refering to my question.

    A new concept is being considered now - the big picture is that we are talking about a complicated system, which contains several processors on different boards, communicating solely through a serial RS232 UART.

    So what we have now, is a Host-PC at one end, several intermediating Uarts

    in the middle and a Nios II at the other far end.

    Theoretically, RedBoot can now play a role again, but maybe the timeouts for the incoming-outgoing messages between the host and the Nios should be changed, or maybe another issues which I am not aware of should be reconsidered...

    Can you think about a solution here? What must be considered?

    Thank you again,

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

    If you&#39;re looking at using a protocol like ymodem to download code, then in principle Redboot should be good for the job (although I&#39;m not clear on your architecture). I haven&#39;t personally used this, but from what I&#39;ve heard you are likely to need to use a slower baud rate than the 115200 used in the Nios II example designs - but other than that, everything should work fine.