flash.md (2382B)
1 # FLASH Driver Configuration {#flash-driver-configuration} 2 3 The FLASH driver can be swapped out depending on the needs of the keyboard, or whether extra hardware is present. 4 5 Driver | Description 6 -----------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- 7 `FLASH_DRIVER = spi` | Supports writing to almost all NOR Flash chips. See the driver section below. 8 9 10 ## SPI FLASH Driver Configuration {#spi-flash-driver-configuration} 11 12 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: 13 14 `config.h` override | Description | Default Value 15 -----------------------------------------------|--------------------------------------------------------------------------------------|----------------- 16 `#define EXTERNAL_FLASH_SPI_SLAVE_SELECT_PIN` | SPI Slave select pin in order to inform that the FLASH is currently being addressed | _none_ 17 `#define EXTERNAL_FLASH_SPI_CLOCK_DIVISOR` | Clock divisor used to divide the peripheral clock to derive the SPI frequency | `8` 18 `#define EXTERNAL_FLASH_PAGE_SIZE` | The Page size of the FLASH in bytes, as specified in the datasheet | `256` 19 `#define EXTERNAL_FLASH_SECTOR_SIZE` | The sector size of the FLASH in bytes, as specified in the datasheet | `(4 * 1024)` 20 `#define EXTERNAL_FLASH_BLOCK_SIZE` | The block size of the FLASH in bytes, as specified in the datasheet | `(64 * 1024)` 21 `#define EXTERNAL_FLASH_SIZE` | The total size of the FLASH in bytes, as specified in the datasheet | `(512 * 1024)` 22 `#define EXTERNAL_FLASH_ADDRESS_SIZE` | The Flash address size in bytes, as specified in datasheet | `3` 23 24 ::: warning 25 All the above default configurations are based on MX25L4006E NOR Flash. 26 :::