Using SPI slave mode boot, the processor consumes boot data from an external SPI host device.
Please find the attached SPI slave booting code for ADSP-21489 processor. This code can be tested across two ADSP-21489 EZ-Kits, where one can be configured as host processor that sends the loader file and other can be act as slave that boots upon receiving the loader file from the Host.
For more information, please refer the 'Slave boot mode' section (Page #: 915/1304) in the ADSP-214xx Hardware reference manual.
https://www.analog.com/media/en/dsp-documentation/processor-manuals/ADSP-214xx_hwr_rev1.1.pdfADSP_21489_SPI_SLAVE_BOOT.zip
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