Unique device ID access API. More...
Data Structures | |
struct | pico_unique_board_id_t |
Unique board identifier. More... | |
Functions | |
void | pico_get_unique_board_id (pico_unique_board_id_t *id_out) |
Get unique ID. More... | |
void | pico_get_unique_board_id_string (char *id_out, uint len) |
Get unique ID in string format. More... | |
Unique device ID access API.
RP2040 does not have an on-board unique identifier (all instances of RP2040 silicon are identical and have no persistent state). However, RP2040 boots from serial NOR flash devices which have a 64-bit unique ID as a standard feature, and there is a 1:1 association between RP2040 and flash, so this is suitable for use as a unique identifier for an RP2040-based board.
This library injects a call to the flash_get_unique_id function from the hardware_flash library, to run before main, and stores the result in a static location which can safely be accessed at any time via pico_get_unique_id().
This avoids some pitfalls of the hardware_flash API, which requires any flash-resident interrupt routines to be disabled when called into.
void pico_get_unique_board_id | ( | pico_unique_board_id_t * | id_out | ) |
Get unique ID.
Get the unique 64-bit device identifier which was retrieved from the external NOR flash device at boot.
On PICO_NO_FLASH builds the unique identifier is set to all 0xEE.
id_out | a pointer to a pico_unique_board_id_t struct, to which the identifier will be written |
void pico_get_unique_board_id_string | ( | char * | id_out, |
uint | len | ||
) |
Get unique ID in string format.
Get the unique 64-bit device identifier which was retrieved from the external NOR flash device at boot, formatted as an ASCII hex string. Will always 0-terminate.
On PICO_NO_FLASH builds the unique identifier is set to all 0xEE.
id_out | a pointer to a char buffer of size len, to which the identifier will be written |
len | the size of id_out. For full serial, len >= 2 * PICO_UNIQUE_BOARD_ID_SIZE_BYTES + 1 |