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Altera_Forum
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21 years ago

Run/Debug with multiple processor

Hi I've made a system with 2x NIOSII/s cpu's with seperate (on-chip) RAM-modules. By now I'm just testing with the "small Hello world" application writing to the Jtag using the Nios...
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Altera_Forum
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21 years ago

This sounds as though you have connected your JTAG UART to both processors. Please try disconnecting it from one of the processors and try again.

If both processors want to send debug text to the host then you should instantiate two JTAG UARTS and connect each one to exactly one processor.

Most of the peripherals shipped with the kitwon't work when connected to more than one processor (unless you are very careful) - for the JTAG UART the problem is that both processors will be interrupted but it will be random which one gets the received character. The other one will get a spurious interrupt if in interrupt driven mode.

The exception to this is of course the 1.1 mutex component which is designed to be connected to multiple processors.