In the schematic of the ADSP-SC584/SC589 evaluation board, a Digital Bus Switch (74CBTLV1G125) is placed between the SPI Flash chip (W25Q128FVSIG) and the ADSP-SC58x processor. This switch is controlled via the TWI module (MCP23017QFN28). For more information, please refer to pages 8 and 24 of the ADSP-SC584/SC589 EZ-Board schematic.
In the Device Programmer project for the ADSP-SC584/SC589, the "ConfigSoftSwitches();" function is used to enable the chip select for the SPI Flash through the TWI interface.
In the custom board schematic, if the SPI2 chip select pin (/CS) is directly connected from the SPI Flash (W25Q128FVSIG) to the ADSP-SC58x processor, soft switch configurations are not required. In this case, comment out the line '#define USE_SOFT_SWITCHES' in the Device Programmer project, rebuild the project, and use the updated driver file 'sc58x_w25q128fv_dpia_Core1.dxe' to flash the custom board.
The ADSP-SC584 EZ-Board Schematic at the following link:
https://www.analog.com/media/en/technical-documentation/eval-board-schematic/ADSP-SC584_EZ_Board_Schematic-Rel_1-4A.pdf
The ADSP-SC589 EZ-Board Schematic at the following link:
https://www.analog.com/media/en/technical-documentation/eval-board-schematic/ADSP-SC589_EZ-Board_Schematic-Rel_2-0B.pdf
Note: If the custom schematic is identical to the evaluation schematic, the existing evaluation driver file "sc58x_w25q128fv_dpia_Core1.dxe" can be used without modifications to the "ConfigSoftSwitches();" function.