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Altera_Forum's avatar
Altera_Forum
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21 years ago

Multiprocessor system problem

Hi everybody,

I've designed a multiprocessor system with two Nios II, f ans s type.I have various peripherals and in particular there is a uart shared between the CPUs. This is the problem: a simple program is running in both the processors and when any processors sends a character to the uart, the system crashes.

any suggestions?

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    21 years ago

    You can only connect a UART to one processor. See previous messages on this forum.

    Think about what happens when an interrupt occurs for why this won't work.
  • Altera_Forum's avatar
    Altera_Forum
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    21 years ago

    Hi wombat,

    thank u for the suggestion. I understand the problem with the interupt, but could this happen even if the uart interupt of one processor is disabled?
  • Altera_Forum's avatar
    Altera_Forum
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    21 years ago

    If you connect the UART interrupt to only one processor then there will probably be slightly different confusion (its a long time since I looked at the UART code).

    If any characters get transmitted at all from the other processor then there may well be some data loss