Booting From Flash

Hi Shmuel,

A flash override file is pretty clearly defined in the Nios II Flash Programmer User Guide. In truth, I'm not 100% sure that it works with EPCS (SPI) flash devices, but it's worth a try.

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How would I store the firmware there and how do I boot from it ( For booting : I know that I will need to set the reset address of each processor to the area of the external flash - but how does the boot loader access the external flash?[/b]

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Well, that depends on what type of flash it is...right? For an EPCS (SPI) flash, the bootloader is stored in a small onchip memory that is part of the epcs_controller component. For the CFI compliant flashes, the bootloader is prepended to the "payload" that you intend to attach.

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Do I need a custom component ? How much additional development will be requried for a non compliant CFI device?[/b]

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It all depends on the type of flash that you decide to use.

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Also do you know what the common type of external (flash) device people use for multi-processor designs? We need a device that we will have the fastest access to since part of our frimware will not fit within the onboard memory of our Altera chip![/b]

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CFI is probably most popular, though I don&#39;t know of many that actually run their code from it.

For your multi-CPU questions, you should browse to AN458 on the following page: http://www.altera.com/literature/lit-an.jsp (http://www.altera.com/literature/lit-an.jsp)

Cheers,

- Brendan