| fis unlock | ||
|---|---|---|
 | 235.3. Flash Image System (FIS) |  |
Name
fis unlock — Unlock flash area
Synopsis
fis unlock {-f flash_address} {-l length}
Arguments
| Name | Type | Description | Default |
|---|---|---|---|
flash_address
| Number | Address of area to be unlocked. | |
length
| Number | Length of area to be unlocked. |
Description
This command is used to unlock a portion of flash memory forcibly, allowing it to be updated. It must be issued for regions which have been locked before the FIS can reuse those portions of flash.
![[Note]](pix/note.png) | Note |
|---|---|
Some flash devices power up in locked state and always need to be manually unlocked before they can be written to. |
Examples
Unlock an area of the flash
RedBoot> fis unlock -f 0xa0040000 -l 0x20000
... Unlock from 0xa0040000-0xa0060000: .| |  | |
| fis lock |  | fis erase |
| 2025-10-02 | eCosPro Non-Commercial Public License |