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app slot

A space in flash that holds one complete firmware image.

An app slot is an app-type partition (ota_0, ota_1, or factory) holding one firmware image; the bootloader selects which slot to run.

Examples

  • The default 4 MB partition table has two app slots, app0 at 0x10000 and app1 at 0x150000, each 0x140000 (1,310,720) bytes.

  • "Maximum is 1310720 bytes" after an Arduino build is the size of one app slot, not the whole flash.

See also

A/B update otadata firmware image
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