requirement of the boot flash

[ycui7]

I am trying to design a miniature USB Audio board. So, obviously I cannot use the boot flash used on the eval kit due to size constraint.

I have looked through many documents but could not find detailed boot flash hardware requirement.

Specifically, the eval board used 133MHz NOR flash. However, I have some difficulty finding small physical size NOR flash at 133MHz. My question is can I use 108MHz NOR Flash? Is there any setting in the .xn file I can use to set the QPSI to a lower speed to accommodate the 108MHz QSPI NOR flash?

[Ross]

The default frequency for the second stage loader is only ~15MHz, with the initial boot loader running slower.

(Checkout the --quad-spi-clock option to xflash to speed it up/slow it down)

[mmar]

Why not XUF208 with included flash.?

[Joe]

If only being used for boot flash then no real speed requirement.

For small size, we use the following part:

https://www.digikey.com/en/products/det ... TR/5804003

Cheers,
Joe