Storage

TIP

RMK has default values for used flash area, check out the default config for your microcontroller. If you're using Rust API, it's recommended to use the default values.

Storage feature is used by saving keymap edits to internal flash.

Storage configuration

If you're using the keyboard.toml, you can set the storage using the following config:

[storage]
# Storage feature is enabled by default
enabled = true
# Start address of local storage, MUST BE start of a sector.
# If start_addr is set to 0(this is the default value), the last `num_sectors` sectors will be used.
start_addr = 0x00000000
# How many sectors are used for storage, the default value is 2
num_sectors = 2
# Clear storage at keyboard boot.
# Set it to true will reset the storage(including keymap, BLE bond info, etc.) at each reboot.
# This option is useful when testing the firmware.
clear_storage = false

You can also edit storage_config field in RmkConfig if you're using Rust API:

// https://github.com/HaoboGu/rmk/blob/main/examples/use_rust/nrf52832_ble/src/main.rs#L48

let storage_config = StorageConfig {
    start_addr: 0x70000,
    num_sectors: 2,
    ..Default::default()
};
let rmk_config = RmkConfig {
    usb_config: keyboard_usb_config,
    vial_config,
    storage_config,
    ..Default::default()
};

When manually setting the storage area, you have to ensure that you have enough flash space for storage feature. If there is not enough space, passing None is acceptable.