SPI Flash API ESP-IDF Version vs Chip-ROM Version

There is a set of SPI Flash drivers in Chip-ROM which you can use by enabling CONFIG_SPI_FLASH_ROM_IMPL. Most of the ESP-IDF SPI Flash driver code are in internal RAM, therefore enabling this option frees some internal RAM usage. Note if you enable this option, this means some SPI Flash driver features and bugfixes that are done in ESP-IDF might not be included in the Chip-ROM version.

Feature Supported by ESP-IDF but Not in Chip-ROM

Bugfixes Introduced in ESP-IDF but Not in Chip-ROM

  • Detected Flash physical size correctly, for larger than 256MBit Flash chips. (Commit ID: b4964279d44f73cce7cfd5cf684567fbdfd6fd9e)

  • Improved SPI1 cs setup timing, otherwise issue may happen on ZB32Q128. (Commit ID: 08f1bbe0c75382f1702e40c941e93314285105d4)

  • Fixed issue that only 128KB virtual address ranges can be mapped to instructions on Flash.