Module efuse 

eFuse (one-time programmable configuration)

Overview

The efuse module provides functionality for reading eFuse data from the chip, allowing access to various chip-specific information such as:

• MAC address
• Chip revision

and more. It is useful for retrieving chip-specific configuration and identification data during runtime.

Examples

Reading interface MAC addresses

use esp_hal::efuse::{self, InterfaceMacAddress};

let mac = efuse::interface_mac_address(InterfaceMacAddress::Station);
println!("MAC: {mac}");
println!("MAC bytes: {:02x?}", mac.as_bytes());

Structs

ChipRevision

Represents the hardware revision.

EfuseFieldunstable

The bit field for get access to efuse data

MacAddress

Hardware (MAC) address.

Enums

InterfaceMacAddress

Interface selection for interface_mac_address.

SetMacErrorunstable

Error indicating issues with setting the MAC address.

Constants

ADC_CALIBunstable

4 bit of ADC calibration

BLK_VERSION_MAJORunstable

BLK_VERSION_MAJOR

BLK_VERSION_MINORunstable

BLK_VERSION_MINOR of BLOCK2

BLOCK0_VERSIONunstable

BLOCK0 efuse version

BLOCK_KEY0unstable

Key0 or user data

BLOCK_KEY1unstable

Key1 or user data

BLOCK_KEY2unstable

Key2 or user data

BLOCK_KEY3unstable

Key3 or user data

BLOCK_KEY4unstable

Key4 or user data

BLOCK_KEY5unstable

Key5 or user data

BLOCK_SYS_DATA2unstable

System data part 2 (reserved)

BLOCK_USR_DATAunstable

User data

CUSTOM_MACunstable

Custom MAC

DISABLE_BLK_VERSION_MAJORunstable

Disables check of blk version major

DISABLE_WAFER_VERSION_MAJORunstable

Disables check of wafer version major

DIS_BOOT_REMAPunstable

Disables capability to Remap RAM to ROM address space

DIS_DCACHEunstable

Set this bit to disable Dcache

DIS_DOWNLOAD_DCACHEunstable

Disables Dcache when SoC is in Download mode

DIS_DOWNLOAD_ICACHEunstable

Disables Icache when SoC is in Download mode

DIS_DOWNLOAD_MANUAL_ENCRYPTunstable

Disables flash encryption when in download boot modes

DIS_DOWNLOAD_MODEunstable

Set this bit to disable all download boot modes

DIS_FORCE_DOWNLOADunstable

Set this bit to disable the function that forces chip into download mode

DIS_ICACHEunstable

Set this bit to disable Icache

DIS_LEGACY_SPI_BOOTunstable

Set this bit to disable Legacy SPI boot mode

DIS_RTC_RAM_BOOTunstable

Reserved

DIS_TWAIunstable

Set this bit to disable the TWAI Controller function

DIS_USBunstable

Set this bit to disable USB OTG function

DIS_USB_DOWNLOAD_MODEunstable

Set this bit to disable use of USB OTG in UART download boot mode

ENABLE_SECURITY_DOWNLOADunstable

Set this bit to enable secure UART download mode (read/write flash only)

FLASH_TPUWunstable

Configures flash startup delay after SoC power-up; in unit of (ms/2). When the value is 15; delay is 7.5 ms

FLASH_TYPEunstable

SPI flash type

FLASH_VERSIONunstable

Flash version

FORCE_SEND_RESUMEunstable

If set; forces ROM code to send an SPI flash resume command during SPI boot

HARD_DIS_JTAGunstable

Hardware disables JTAG permanently

KEY_PURPOSE_0unstable

Purpose of KEY0

KEY_PURPOSE_1unstable

Purpose of KEY1

KEY_PURPOSE_2unstable

Purpose of KEY2

KEY_PURPOSE_3unstable

Purpose of KEY3

KEY_PURPOSE_4unstable

Purpose of KEY4

KEY_PURPOSE_5unstable

Purpose of KEY5

KEY_PURPOSE_6unstable

Purpose of KEY6

MAC0unstable

MAC address

MAC1unstable

MAC address

OPTIONAL_UNIQUE_IDunstable

Optional unique 128-bit ID

PIN_POWER_SELECTIONunstable

Set default power supply for GPIO33-GPIO37; set when SPI flash is initialized

PKG_VERSIONunstable

Package version

PSRAM_VERSIONunstable

PSRAM version

RD_DISunstable

Disable reading from BlOCK4-10

RESERVED_0_162unstable

reserved

RESERVED_1_123unstable

reserved

RESERVED_1_135unstable

reserved

RESERVED_3_192unstable

reserved

RESERVED_3_248unstable

reserved

RPT4_RESERVED1unstable

Reserved (used for four backups method)

RPT4_RESERVED2unstable

Reserved (used for four backups method)

RPT4_RESERVED3unstable

Reserved (used for four backups method)

RPT4_RESERVED5unstable

Reserved (used for four backups method)

RTCCALIB_V1IDX_A10Hunstable

RTCCALIB_V1IDX_A10Lunstable

RTCCALIB_V1IDX_A11Hunstable

RTCCALIB_V1IDX_A11Lunstable

RTCCALIB_V1IDX_A12Hunstable

RTCCALIB_V1IDX_A12Lunstable

RTCCALIB_V1IDX_A13Hunstable

RTCCALIB_V1IDX_A13Lunstable

RTCCALIB_V1IDX_A20Hunstable

RTCCALIB_V1IDX_A20Lunstable

RTCCALIB_V1IDX_A21Hunstable

RTCCALIB_V1IDX_A21Lunstable

RTCCALIB_V1IDX_A22Hunstable

RTCCALIB_V1IDX_A22Lunstable

RTCCALIB_V1IDX_A23Hunstable

RTCCALIB_V1IDX_A23Lunstable

SECURE_BOOT_AGGRESSIVE_REVOKEunstable

Set this bit to enable aggressive secure boot key revocation mode

SECURE_BOOT_ENunstable

Set this bit to enable secure boot

SECURE_BOOT_KEY_REVOKE0unstable

Revoke 1st secure boot key

SECURE_BOOT_KEY_REVOKE1unstable

Revoke 2nd secure boot key

SECURE_BOOT_KEY_REVOKE2unstable

Revoke 3rd secure boot key

SECURE_VERSIONunstable

Secure version (used by ESP-IDF anti-rollback feature)

SOFT_DIS_JTAGunstable

Software disables JTAG. When software disabled; JTAG can be activated temporarily by HMAC peripheral

SPI_BOOT_CRYPT_CNTunstable

Enables flash encryption when 1 or 3 bits are set and disabled otherwise

SPI_PAD_CONFIG_CLKunstable

SPI_PAD_configure CLK

SPI_PAD_CONFIG_CSunstable

SPI_PAD_configure CS

SPI_PAD_CONFIG_Dunstable

SPI_PAD_configure D(D0)

SPI_PAD_CONFIG_D4unstable

SPI_PAD_configure D4

SPI_PAD_CONFIG_D5unstable

SPI_PAD_configure D5

SPI_PAD_CONFIG_D6unstable

SPI_PAD_configure D6

SPI_PAD_CONFIG_D7unstable

SPI_PAD_configure D7

SPI_PAD_CONFIG_DQSunstable

SPI_PAD_configure DQS

SPI_PAD_CONFIG_HDunstable

SPI_PAD_configure HD(D3)

SPI_PAD_CONFIG_Qunstable

SPI_PAD_configure Q(D1)

SPI_PAD_CONFIG_WPunstable

SPI_PAD_configure WP(D2)

SYS_DATA_PART0_2unstable

Stores the second part of the zeroth part of system data

TEMP_CALIBunstable

Temperature calibration data

UART_PRINT_CHANNELunstable

Selects the default UART for printing boot messages

UART_PRINT_CONTROLunstable

Set the default UART boot message output mode

USB_DREFHunstable

Controls single-end input threshold vrefh; 1.76 V to 2 V with step of 80 mV; stored in eFuse

USB_DREFLunstable

Controls single-end input threshold vrefl; 0.8 V to 1.04 V with step of 80 mV; stored in eFuse

USB_EXCHG_PINSunstable

Set this bit to exchange USB D+ and D- pins

USB_EXT_PHY_ENABLEunstable

Set this bit to enable external USB PHY

USB_FORCE_NOPERSISTunstable

If set; forces USB BVALID to 1

VDD_SPI_DCAPunstable

Prevents SPI regulator from overshoot

VDD_SPI_DCURLIMunstable

Tunes the current limit threshold of SPI regulator when tieh=0; about 800 mA/(8+d)

VDD_SPI_DREFHunstable

SPI regulator high voltage reference

VDD_SPI_DREFLunstable

SPI regulator low voltage reference

VDD_SPI_DREFMunstable

SPI regulator medium voltage reference

VDD_SPI_ENCURLIMunstable

Set SPI regulator to 1 to enable output current limit

VDD_SPI_EN_INITunstable

Set SPI regulator to 0 to configure init[1:0]=0

VDD_SPI_FORCEunstable

Set this bit to use XPD_VDD_PSI_REG and VDD_SPI_TIEH to configure VDD_SPI LDO

VDD_SPI_INITunstable

Adds resistor from LDO output to ground

VDD_SPI_MODECURLIMunstable

SPI regulator switches current limit mode

VDD_SPI_TIEHunstable

If VDD_SPI_FORCE is 1; determines VDD_SPI voltage

VDD_SPI_XPDunstable

If VDD_SPI_FORCE is 1; this value determines if the VDD_SPI regulator is powered on

WAFER_VERSION_MAJORunstable

WAFER_VERSION_MAJOR

WAFER_VERSION_MINOR_HIunstable

WAFER_VERSION_MINOR most significant bit

WAFER_VERSION_MINOR_LOunstable

WAFER_VERSION_MINOR least significant bits

WDT_DELAY_SELunstable

RTC watchdog timeout threshold; in unit of slow clock cycle

WR_DISunstable

Disable programming of individual eFuses

Functions

base_mac_addressunstable

Returns the base MAC address programmed into eFuse during manufacturing.

chip_revision

Returns the hardware revision.

flash_encryptionunstable

Get status of SPI boot encryption.

interface_mac_address

Returns the MAC address for a specific interface, derived from the base MAC.

major_chip_versionunstable

Returns the major hardware revision

minor_chip_versionunstable

Returns the minor hardware revision

override_mac_addressunstable

Overrides the base MAC address used by interface_mac_address.

read_bitunstable

Read bit value.

read_field_leunstable

Read field value in a little-endian order

rwdt_multiplierunstable

Get the multiplier for the timeout value of the RWDT STAGE 0 register.