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Altera_Forum
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16 years ago

Booting two Nios 2 processors on same FPGA

Hello , My design has 2 NIOS 2 processors. I want to load a boot image into each of the processors. I want to load it using the boot copier by means of EPCS method. I have tried th...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

A couple of ideas:

1 - Let one processor boot first holding the other processor in reset via the cpu_reset_request signal.

2 - Consider using a small custom peripheral connected to each CPU with a unique ID. Your bootloader can read this unique ID to determine any processor specific boot procedures that need to be performed (like which address in the EPCS device to grab the code from).

3 - You don't have to have both CPUs boot from the EPCS Controller directly. You could have one processor use the EPCS controller as it's reset address. The second processor could simply have a piece of onchip memory that it boots from. You might have the second processor sit there and wait for a signal from the first processor; at which point it would begin it's bootloading process of copying needed data from the EPCS device.

Just some ideas...

Jake