Here's a patch that fixes inconsistencies we discovered with a Linux PC writing to the SPI flash of VS1010D using USB mass storage in runlevel 4. The problem may occur in other operating systems also, so this patch should be applied to all VS1010D boards that have an SPI flash installed.
To install the patch, place the patch file "boot.dlx" into the root of your system disk, typically the SPI flash itself. It's a good idea to have this patch both in the root of the SD card you use for development, and in the root of the SPI flash, so the patch is loaded no matter which device the VS1010D uses as the system disk.
Please note that the SPI flash is used as the system disk only if it contains a SYS folder in the root. If the SPI flash does not have the "SYS" folder, then the boot.dlx patch is still loaded from the SD card, not from the SPI flash.
When the patch is succesfully loaded, you will see a console notification like the one below:
For more information, please see the source code of the patch inside the .zip package.VS1010D VSOS 4.20
VS1010D patch SPI flash write
Updated 2020-11-02, version 2.
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