FLASH Driver Configuration {#flash-driver-configuration}

The FLASH driver can be swapped out depending on the needs of the keyboard, or whether extra hardware is present.

Driver | Description -----------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- FLASH_DRIVER = spi | Supports writing to almost all NOR Flash chips. See the driver section below.

SPI FLASH Driver Configuration {#spi-flash-driver-configuration}

Currently QMK supports almost all NOR Flash chips over SPI. As such, requires a working spi_master driver configuration. You can override the driver configuration via your config.h:

config.h override | Description | Default Value -----------------------------------------------|--------------------------------------------------------------------------------------|----------------- #define EXTERNAL_FLASH_SPI_SLAVE_SELECT_PIN | SPI Slave select pin in order to inform that the FLASH is currently being addressed | none #define EXTERNAL_FLASH_SPI_CLOCK_DIVISOR | Clock divisor used to divide the peripheral clock to derive the SPI frequency | 8 #define EXTERNAL_FLASH_PAGE_SIZE | The Page size of the FLASH in bytes, as specified in the datasheet | 256 #define EXTERNAL_FLASH_SECTOR_SIZE | The sector size of the FLASH in bytes, as specified in the datasheet | (4 * 1024) #define EXTERNAL_FLASH_BLOCK_SIZE | The block size of the FLASH in bytes, as specified in the datasheet | (64 * 1024) #define EXTERNAL_FLASH_SIZE | The total size of the FLASH in bytes, as specified in the datasheet | (512 * 1024) #define EXTERNAL_FLASH_ADDRESS_SIZE | The Flash address size in bytes, as specified in datasheet | 3

::: warning All the above default configurations are based on MX25L4006E NOR Flash. :::