Hello @giwonKIM and welcome to the Community :),
The OCTOSPI provides a flexible hardware interface, that enables the support of multiple hardware configurations: Single-SPI (legacy SPI), Dual-SPI, Quad-SPI, Dual-quad-SPI and Octo-SPI. Please take a look at FAQ: Does OctoSPI interface support QuadSPI memories?
To set and configure the OCTOSPI interface , I recommend you to refer to AN5050 precisely "6 OCTOSPI application examples" section.
Note that, the OctoSPI work only as a master, for that this interface supports the Single-SPI (legacy SPI).
For more information, I advise you to take a look at RM0468 section OCTOSPI regular-command protocol Section.
I think this discussion can help you.
I hope this answer your request!
Thank you
Kaouthar
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