Forum Discussion

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

The problem of multiprocessor of FPGA

Guys, we've been just trying to deal with a problem of multiprocessor of FPGA. The problem is, the project could only work if we use NIOS II/e. If we use some other types of processors, it does not work. So would you please tell me the reasons?

The tools we use are NIOS IDE 8.1, Quartus II8.1.

Thanks.

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    When we used two NiosII/e processors in our SOPC Builder, it worked well, but when we changed either processor to NiosII/s, neither would work well. For example, we used the two processors to control two leds respectively, neither led works.

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    Do the two softwares use different parts of memory? (including stack and heap)

    Do you use IOWR instructions to access the LEDs?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    You should use a hardware mutex (setup in SOPC Builder) to provide mutually exclusive access to the LED. Then each Nios II processor must use the mutex API to gain access to the LED resource before attempting to modify it.

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    As Daixiwen alludes to, make sure that all of your peripheral registers are mapped to non-cached memory areas.