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rhulmerhulme
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Add pico_unique_id library to host platform
Fixes #2750
1 parent 299fb7d commit 624bf22

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6 files changed

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‎src/common/pico_base_headers/BUILD.bazel‎

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@@ -95,6 +95,7 @@ cc_library(
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"//src/host/hardware_sync:__pkg__",
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"//src/host/hardware_timer:__pkg__",
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"//src/host/pico_platform:__pkg__",
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"//src/host/pico_unique_id:__pkg__",
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"//src/rp2040/boot_stage2:__pkg__",
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"//src/rp2040/pico_platform:__pkg__",
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"//src/rp2350/boot_stage2:__pkg__",

‎src/host.cmake‎

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@@ -38,6 +38,7 @@ include (${CMAKE_DIR}/no_hardware.cmake)
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pico_add_subdirectory(${HOST_DIR}/pico_stdio)
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pico_add_subdirectory(${HOST_DIR}/pico_stdlib)
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pico_add_subdirectory(${HOST_DIR}/pico_time_adapter)
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pico_add_subdirectory(${HOST_DIR}/pico_unique_id)
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unset(CMAKE_DIR)
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unset(COMMON_DIR)

‎src/host/pico_unique_id/BUILD.bazel‎

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package(default_visibility = ["//visibility:public"])
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cc_library(
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name = "pico_unique_id",
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srcs = ["unique_id.c"],
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hdrs = ["include/pico/unique_id.h"],
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includes = ["include"],
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target_compatible_with = ["//bazel/constraint:host"],
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deps = [
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"//src/common/pico_base_headers",
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"//src/host/pico_platform",
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],
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)

‎src/host/pico_unique_id/CMakeLists.txt‎

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pico_add_library(pico_unique_id)
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target_sources(pico_unique_id INTERFACE
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${CMAKE_CURRENT_LIST_DIR}/unique_id.c
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)
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target_include_directories(pico_unique_id_headers SYSTEM INTERFACE ${CMAKE_CURRENT_LIST_DIR}/include)
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target_link_libraries(pico_unique_id_headers INTERFACE pico_base_headers)

‎src/host/pico_unique_id/include/pico/unique_id.h‎

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/*
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* Copyright (c) 2021 Raspberry Pi (Trading) Ltd.
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*
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* SPDX-License-Identifier: BSD-3-Clause
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*/
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#ifndef _PICO_UNIQUE_ID_H
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#define _PICO_UNIQUE_ID_H
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#include "pico.h"
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#ifdef __cplusplus
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extern "C" {
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#endif
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/** \file pico/unique_id.h
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* \defgroup pico_unique_id pico_unique_id
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*
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* \brief Unique device ID access API
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*
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* \if rp2040_specific
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* RP2040 does not have an on-board unique identifier (all instances of RP2040
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* silicon are identical and have no persistent state). However, RP2040 boots
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* from serial NOR flash devices which have at least a 64-bit unique ID as a standard
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* feature, and there is a 1:1 association between RP2040 and flash, so this
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* is suitable for use as a unique identifier for an RP2040-based board.
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*
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* This library injects a call to the flash_get_unique_id function from the
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* hardware_flash library, to run before main, and stores the result in a
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* static location which can safely be accessed at any time via
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* pico_get_unique_id().
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*
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* This avoids some pitfalls of the hardware_flash API, which requires any
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* flash-resident interrupt routines to be disabled when called into.
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* \endif
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*
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* \if rp2350_specific
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* On boards using RP2350, the unique identifier is read from OTP memory on boot.
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* \endif
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*/
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#define PICO_UNIQUE_BOARD_ID_SIZE_BYTES 8
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/**
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* \brief Static initialization order
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* \ingroup pico_unique_id
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*
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* This defines the init_priority of the pico_unique_id. By default, it is 1000. The valid range is
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* from 101-65535. Set it to -1 to set the priority to none, thus putting it after 65535. Changing
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* this value will initialize the unique_id earlier or later in the static initialization order.
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* This is most useful for C++ consumers of the pico-sdk.
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*
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* See https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-constructor-function-attribute
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* and https://gcc.gnu.org/onlinedocs/gcc/C_002b_002b-Attributes.html#index-init_005fpriority-variable-attribute
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*
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* Here is an example of C++ static initializers that will run before, and then after, pico_unique_id is loaded:
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*
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* [[gnu::init_priority(500)]] my_class before_instance;
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* [[gnu::init_priority(2000)]] my_class after_instance;
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*
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*/
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#ifndef PICO_UNIQUE_BOARD_ID_INIT_PRIORITY
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#define PICO_UNIQUE_BOARD_ID_INIT_PRIORITY 1000
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#endif
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/**
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* \brief Unique board identifier
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* \ingroup pico_unique_id
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*
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* This structure contains an array of PICO_UNIQUE_BOARD_ID_SIZE_BYTES identifier bytes suitable for
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* holding the unique identifier for the device.
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*
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* \if rp2040_specific
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* On an RP2040-based board, the unique identifier is retrieved from the external NOR flash device at boot,
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* or for PICO_NO_FLASH builds the unique identifier is set to all 0xEE.
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* \endif
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*
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* \if rp2350_specific
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* On an RP2350-based board, the unique identifier is retrieved from OTP memory at boot.
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* \endif
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*
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*/
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typedef struct {
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uint8_t id[PICO_UNIQUE_BOARD_ID_SIZE_BYTES];
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} pico_unique_board_id_t;
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/*! \brief Get unique ID
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* \ingroup pico_unique_id
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*
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* Get the unique 64-bit device identifier.
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*
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* \if rp2040_specific
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* On an RP2040-based board, the unique identifier is retrieved from the external NOR flash device at boot,
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* or for PICO_NO_FLASH builds the unique identifier is set to all 0xEE.
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* \endif
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*
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* \if rp2350_specific
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* On an RP2350-based board, the unique identifier is retrieved from OTP memory at boot.
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* \endif
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*
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* \param id_out a pointer to a pico_unique_board_id_t struct, to which the identifier will be written
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*/
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void pico_get_unique_board_id(pico_unique_board_id_t *id_out);
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/*! \brief Get unique ID in string format
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* \ingroup pico_unique_id
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*
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* Get the unique 64-bit device identifier formatted as a 0-terminated ASCII hex string.
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*
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* \if rp2040_specific
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* On an RP2040-based board, the unique identifier is retrieved from the external NOR flash device at boot,
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* or for PICO_NO_FLASH builds the unique identifier is set to all 0xEE.
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* \endif
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*
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* \if rp2350_specific
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* On an RP2350-based board, the unique identifier is retrieved from OTP memory at boot.
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* \endif
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*
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* \param id_out a pointer to a char buffer of size len, to which the identifier will be written
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* \param len the size of id_out. For full serial, len >= 2 * PICO_UNIQUE_BOARD_ID_SIZE_BYTES + 1
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*/
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void pico_get_unique_board_id_string(char *id_out, uint len);
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#ifdef __cplusplus
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}
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#endif
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#endif

‎src/host/pico_unique_id/unique_id.c‎

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/*
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* Copyright (c) 2021 Raspberry Pi (Trading) Ltd.
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*
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* SPDX-License-Identifier: BSD-3-Clause
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*/
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#include "pico/unique_id.h"
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static pico_unique_board_id_t retrieved_id;
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#if PICO_UNIQUE_BOARD_ID_INIT_PRIORITY == -1
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#define PICO_UNIQUE_BOARD_ID_INIT_ATTRIBUTES constructor
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#else
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#define PICO_UNIQUE_BOARD_ID_INIT_ATTRIBUTES constructor(PICO_UNIQUE_BOARD_ID_INIT_PRIORITY)
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#endif
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static void __attribute__((PICO_UNIQUE_BOARD_ID_INIT_ATTRIBUTES)) _retrieve_unique_id_on_boot(void) {
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for (int i = 0; i < PICO_UNIQUE_BOARD_ID_SIZE_BYTES; i++) {
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retrieved_id.id[i] = 0xa0 + i;
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}
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}
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PICO_WEAK_FUNCTION_DEF(pico_get_unique_board_id)
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void PICO_WEAK_FUNCTION_IMPL_NAME(pico_get_unique_board_id)(pico_unique_board_id_t *id_out) {
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*id_out = retrieved_id;
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}
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PICO_WEAK_FUNCTION_DEF(pico_get_unique_board_id_string)
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void PICO_WEAK_FUNCTION_IMPL_NAME(pico_get_unique_board_id_string)(char *id_out, uint len) {
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assert(len > 0);
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size_t i;
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// Generate hex one nibble at a time
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for (i = 0; (i < len - 1) && (i < PICO_UNIQUE_BOARD_ID_SIZE_BYTES * 2); i++) {
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int nibble = (retrieved_id.id[i/2] >> (4 - 4 * (i&1))) & 0xf;
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id_out[i] = (char)(nibble < 10 ? nibble + '0' : nibble + 'A' - 10);
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}
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id_out[i] = 0;
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}

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