Summary

The espefuse.py summary command reads the eFuses from the chip and outputs them in text or json format. It is also possible to save it to a file. The command also supports eFuse filtering by name.

Optional arguments:

  • --format - Select the summary format:
    • summary - text format (default option).

    • json - json format. Usage --format json.

    • value_only - only the value of the eFuse specified as an argument will be displayed. For more information, refer to the Filtering eFuses section.

  • --file - File to save the efuse summary. Usage --file efuses.json.

  • List of eFuses to filter. For more information, refer to the Filtering eFuses section.

Text Format Summary

The text format of summary consists of 3 main columns:

  1. This column consists of the eFuse name and additional information: the block name associated with this eFuse field and encoding errors (if any).

  2. Description of eFuse field.

  3. This column has human readable value, read/write protection status, raw value (hexadecimal or binary).

Read and Write Protection Status

The R/W output indicates a protection status of a specific eFuse field/block:

  • -/W indicates that read protection is set. Value of such eFuse field will always show all-zeroes, even though hardware may use the correct value. In espefuse v2.6 and newer, read-protected eFuse values are displayed as question marks (??). On earlier versions, they are displayed as zeroes.

    BLOCK1 (BLOCK1):
    = ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? -/W
    
  • R/- indicates that write protection is set. No further bits can be set.

  • -/- means both read and write protection are set.

Some eFuses have no protection at all, and some eFuses have only one read or write protection. There is no mark in the summary to expose it.

Display Efuse Summary

The eFuse summary may vary from version to version of this tool and differ for different chips. Below is the summary for the ESP32-S3 chip.

For details on the meaning of each eFuse value, refer to the Technical Reference Manual.

> espefuse.py -p PORT summary

Connecting....
Detecting chip type... ESP32-S3

=== Run "summary" command ===
EFUSE_NAME (Block) Description  = [Meaningful Value] [Readable/Writeable] (Hex Value)
----------------------------------------------------------------------------------------
Config fuses:
WR_DIS (BLOCK0)                                    Disable programming of individual eFuses           = 0 R/W (0x00000000)
RD_DIS (BLOCK0)                                    Disable reading from BlOCK4-10                     = 0 R/W (0b0000000)
DIS_ICACHE (BLOCK0)                                Set this bit to disable Icache                     = False R/W (0b0)
DIS_DCACHE (BLOCK0)                                Set this bit to disable Dcache                     = False R/W (0b0)
DIS_TWAI (BLOCK0)                                  Set this bit to disable CAN function               = False R/W (0b0)
DIS_APP_CPU (BLOCK0)                               Disable app cpu                                    = False R/W (0b0)
DIS_DIRECT_BOOT (BLOCK0)                           Disable direct boot mode                           = False R/W (0b0)
UART_PRINT_CONTROL (BLOCK0)                        Set the default UART boot message output mode      = Enable R/W (0b00)
PIN_POWER_SELECTION (BLOCK0)                       Set default power supply for GPIO33-GPIO37; set wh = VDD3P3_CPU R/W (0b0)
                                                   en SPI flash is initialized
BLOCK_USR_DATA (BLOCK3)                            User data
= 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 R/W
BLOCK_SYS_DATA2 (BLOCK10)                          System data part 2 (reserved)
= 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 R/W

Flash fuses:
FLASH_TPUW (BLOCK0)                                Configures flash waiting time after power-up; in u = 0 R/W (0x0)
                                                   nit of ms. If the value is less than 15; the waiti
                                                   ng time is the configurable value.  Otherwise; the
                                                    waiting time is twice the configurable value
FLASH_ECC_MODE (BLOCK0)                            Flash ECC mode in ROM                              = 16to18 byte R/W (0b0)
FLASH_TYPE (BLOCK0)                                SPI flash type                                     = 4 data lines R/W (0b0)
FLASH_PAGE_SIZE (BLOCK0)                           Set Flash page size                                = 0 R/W (0b00)
FLASH_ECC_EN (BLOCK0)                              Set 1 to enable ECC for flash boot                 = False R/W (0b0)
FORCE_SEND_RESUME (BLOCK0)                         Set this bit to force ROM code to send a resume co = False R/W (0b0)
                                                   mmand during SPI boot

Identity fuses:
DISABLE_WAFER_VERSION_MAJOR (BLOCK0)               Disables check of wafer version major              = False R/W (0b0)
DISABLE_BLK_VERSION_MAJOR (BLOCK0)                 Disables check of blk version major                = False R/W (0b0)
WAFER_VERSION_MINOR_LO (BLOCK1)                    WAFER_VERSION_MINOR least significant bits         = 0 R/W (0b000)
PKG_VERSION (BLOCK1)                               Package version                                    = 0 R/W (0b000)
BLK_VERSION_MINOR (BLOCK1)                         BLK_VERSION_MINOR                                  = 0 R/W (0b000)
WAFER_VERSION_MINOR_HI (BLOCK1)                    WAFER_VERSION_MINOR most significant bit           = False R/W (0b0)
WAFER_VERSION_MAJOR (BLOCK1)                       WAFER_VERSION_MAJOR                                = 0 R/W (0b00)
OPTIONAL_UNIQUE_ID (BLOCK2)                        Optional unique 128-bit ID
= 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 R/W
BLK_VERSION_MAJOR (BLOCK2)                         BLK_VERSION_MAJOR of BLOCK2                        = No calib R/W (0b00)
WAFER_VERSION_MINOR (BLOCK0)                       calc WAFER VERSION MINOR = WAFER_VERSION_MINOR_HI  = 0 R/W (0x0)
                                                   << 3 + WAFER_VERSION_MINOR_LO (read only)

Jtag fuses:
SOFT_DIS_JTAG (BLOCK0)                             Set these bits to disable JTAG in the soft way (od = 0 R/W (0b000)
                                                   d number 1 means disable ). JTAG can be enabled in
                                                    HMAC module
DIS_PAD_JTAG (BLOCK0)                              Set this bit to disable JTAG in the hard way. JTAG = False R/W (0b0)
                                                    is disabled permanently
STRAP_JTAG_SEL (BLOCK0)                            Set this bit to enable selection between usb_to_jt = False R/W (0b0)
                                                   ag and pad_to_jtag through strapping gpio10 when b
                                                   oth reg_dis_usb_jtag and reg_dis_pad_jtag are equa
                                                   l to 0

Mac fuses:
MAC (BLOCK1)                                       MAC address
= 7c:df:a1:e0:00:58 (OK) R/W
CUSTOM_MAC (BLOCK3)                                Custom MAC
= 00:00:00:00:00:00 (OK) R/W

Security fuses:
DIS_DOWNLOAD_ICACHE (BLOCK0)                       Set this bit to disable Icache in download mode (b = False R/W (0b0)
                                                   oot_mode[3:0] is 0; 1; 2; 3; 6; 7)
DIS_DOWNLOAD_DCACHE (BLOCK0)                       Set this bit to disable Dcache in download mode (  = False R/W (0b0)
                                                   boot_mode[3:0] is 0; 1; 2; 3; 6; 7)
DIS_FORCE_DOWNLOAD (BLOCK0)                        Set this bit to disable the function that forces c = False R/W (0b0)
                                                   hip into download mode
DIS_DOWNLOAD_MANUAL_ENCRYPT (BLOCK0)               Set this bit to disable flash encryption when in d = False R/W (0b0)
                                                   ownload boot modes
SPI_BOOT_CRYPT_CNT (BLOCK0)                        Enables flash encryption when 1 or 3 bits are set  = Disable R/W (0b000)
                                                   and disabled otherwise
SECURE_BOOT_KEY_REVOKE0 (BLOCK0)                   Revoke 1st secure boot key                         = False R/W (0b0)
SECURE_BOOT_KEY_REVOKE1 (BLOCK0)                   Revoke 2nd secure boot key                         = False R/W (0b0)
SECURE_BOOT_KEY_REVOKE2 (BLOCK0)                   Revoke 3rd secure boot key                         = False R/W (0b0)
KEY_PURPOSE_0 (BLOCK0)                             Purpose of Key0                                    = USER R/W (0x0)
KEY_PURPOSE_1 (BLOCK0)                             Purpose of Key1                                    = USER R/W (0x0)
KEY_PURPOSE_2 (BLOCK0)                             Purpose of Key2                                    = USER R/W (0x0)
KEY_PURPOSE_3 (BLOCK0)                             Purpose of Key3                                    = USER R/W (0x0)
KEY_PURPOSE_4 (BLOCK0)                             Purpose of Key4                                    = USER R/W (0x0)
KEY_PURPOSE_5 (BLOCK0)                             Purpose of Key5                                    = USER R/W (0x0)
SECURE_BOOT_EN (BLOCK0)                            Set this bit to enable secure boot                 = False R/W (0b0)
SECURE_BOOT_AGGRESSIVE_REVOKE (BLOCK0)             Set this bit to enable revoking aggressive secure  = False R/W (0b0)
                                                   boot
DIS_DOWNLOAD_MODE (BLOCK0)                         Set this bit to disable download mode (boot_mode[3 = False R/W (0b0)
                                                   :0] = 0; 1; 2; 3; 6; 7)
ENABLE_SECURITY_DOWNLOAD (BLOCK0)                  Set this bit to enable secure UART download mode   = False R/W (0b0)
SECURE_VERSION (BLOCK0)                            Secure version (used by ESP-IDF anti-rollback feat = 0 R/W (0x0000)
                                                   ure)
BLOCK_KEY0 (BLOCK4)
Purpose: USER
            Key0 or user data
= 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 R/W
BLOCK_KEY1 (BLOCK5)
Purpose: USER
            Key1 or user data
= 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 R/W
BLOCK_KEY2 (BLOCK6)
Purpose: USER
            Key2 or user data
= 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 R/W
BLOCK_KEY3 (BLOCK7)
Purpose: USER
            Key3 or user data
= 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 R/W
BLOCK_KEY4 (BLOCK8)
Purpose: USER
            Key4 or user data
= 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 R/W
BLOCK_KEY5 (BLOCK9)
Purpose: USER
            Key5 or user data
= 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 R/W

Spi Pad fuses:
SPI_PAD_CONFIG_CLK (BLOCK1)                        SPI_PAD_configure CLK                              = 0 R/W (0b000000)
SPI_PAD_CONFIG_Q (BLOCK1)                          SPI_PAD_configure Q(D1)                            = 0 R/W (0b000000)
SPI_PAD_CONFIG_D (BLOCK1)                          SPI_PAD_configure D(D0)                            = 0 R/W (0b000000)
SPI_PAD_CONFIG_CS (BLOCK1)                         SPI_PAD_configure CS                               = 0 R/W (0b000000)
SPI_PAD_CONFIG_HD (BLOCK1)                         SPI_PAD_configure HD(D3)                           = 0 R/W (0b000000)
SPI_PAD_CONFIG_WP (BLOCK1)                         SPI_PAD_configure WP(D2)                           = 0 R/W (0b000000)
SPI_PAD_CONFIG_DQS (BLOCK1)                        SPI_PAD_configure DQS                              = 0 R/W (0b000000)
SPI_PAD_CONFIG_D4 (BLOCK1)                         SPI_PAD_configure D4                               = 0 R/W (0b000000)
SPI_PAD_CONFIG_D5 (BLOCK1)                         SPI_PAD_configure D5                               = 0 R/W (0b000000)
SPI_PAD_CONFIG_D6 (BLOCK1)                         SPI_PAD_configure D6                               = 0 R/W (0b000000)
SPI_PAD_CONFIG_D7 (BLOCK1)                         SPI_PAD_configure D7                               = 0 R/W (0b000000)

Usb fuses:
DIS_USB_OTG (BLOCK0)                               Set this bit to disable USB function               = False R/W (0b0)
USB_EXCHG_PINS (BLOCK0)                            Set this bit to exchange USB D+ and D- pins        = False R/W (0b0)
USB_EXT_PHY_ENABLE (BLOCK0)                        Set this bit to enable external PHY                = False R/W (0b0)
DIS_USB_JTAG (BLOCK0)                              Set this bit to disable function of usb switch to  = False R/W (0b0)
                                                   jtag in module of usb device
DIS_USB_SERIAL_JTAG (BLOCK0)                       Set this bit to disable usb device                 = False R/W (0b0)
USB_PHY_SEL (BLOCK0)                               This bit is used to switch internal PHY and extern
= internal PHY is assigned to USB Device while external PHY is assigned to USB OTG R/W (0b0)
                                                   al PHY for USB OTG and USB Device
DIS_USB_SERIAL_JTAG_ROM_PRINT (BLOCK0)             USB printing                                       = Enable R/W (0b0)
DIS_USB_SERIAL_JTAG_DOWNLOAD_MODE (BLOCK0)         Set this bit to disable UART download mode through = False R/W (0b0)
                                                    USB
DIS_USB_OTG_DOWNLOAD_MODE (BLOCK0)                 Set this bit to disable download through USB-OTG   = False R/W (0b0)

Vdd fuses:
VDD_SPI_XPD (BLOCK0)                               SPI regulator power up signal                      = False R/W (0b0)
VDD_SPI_TIEH (BLOCK0)                              If VDD_SPI_FORCE is 1; determines VDD_SPI voltage
= VDD_SPI connects to 1.8 V LDO R/W (0b0)
VDD_SPI_FORCE (BLOCK0)                             Set this bit and force to use the configuration of = False R/W (0b0)
                                                    eFuse to configure VDD_SPI

Wdt fuses:
WDT_DELAY_SEL (BLOCK0)                             RTC watchdog timeout threshold; in unit of slow cl = 40000 R/W (0b00)
                                                   ock cycle

Flash voltage (VDD_SPI) determined by GPIO45 on reset (GPIO45=High: VDD_SPI pin is powered from internal 1.8V LDO
GPIO45=Low or NC: VDD_SPI pin is powered directly from VDD3P3_RTC_IO via resistor Rspi. Typically this voltage is 3.3 V).

Json Format Summary

The json representation of eFuses for the ESP32 chip is shown below.

> espefuse.py summary --format json

{
    "ABS_DONE_0": {
        "bit_len": 1,
        "block": 0,
        "category": "security",
        "description": "Secure boot V1 is enabled for bootloader image",
        "efuse_type": "bool",
        "name": "ABS_DONE_0",
        "pos": 4,
        "readable": true,
        "value": false,
        "word": 6,
        "writeable": true
    },
    "BLOCK1": {
        "bit_len": 256,
        "block": 1,
        "category": "security",
        "description": "Flash encryption key",
        "efuse_type": "bytes:32",
        "name": "BLOCK1",
        "pos": 0,
        "readable": true,
        "value": "00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00",
        "word": 0,
        "writeable": true
    },
...
    "CODING_SCHEME": {
        "bit_len": 2,
        "block": 0,
        "category": "efuse",
        "description": "Efuse variable block length scheme",
        "efuse_type": "uint:2",
        "name": "CODING_SCHEME",
        "pos": 0,
        "readable": true,
        "value": "NONE (BLK1-3 len=256 bits)",
        "word": 6,
        "writeable": true
    },
....
}

Save Json Format Summary To File

> espefuse.py summary --format json --file efuses.json

Connecting..........
Detecting chip type... Unsupported detection protocol, switching and trying again...
Connecting....
Detecting chip type... ESP32

=== Run "summary" command ===
Saving efuse values to efuses.json

Filtering Efuses and Displaying Only the Value

The espefuse.py summary command supports filtering eFuses by name. The eFuses to filter needs to be specified as positional arguments. If no eFuses are specified, complete summary will be displayed. Example:

> espefuse.py summary ABS_DONE_0 BLOCK1

=== Run "summary" command ===
EFUSE_NAME (Block) Description  = [Meaningful Value] [Readable/Writeable] (Hex Value)
----------------------------------------------------------------------------------------
Security fuses:
ABS_DONE_0 (BLOCK0)                                Secure boot V1 is enabled for bootloader image     = False R/W (0b0)
BLOCK1 (BLOCK1)                                    Flash encryption key
= 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 R/W

If --format value_only is specified, only the value of the eFuse specified as an argument will be displayed. Only one eFuse can be specified as an argument for this format. Example:

> espefuse.py summary --format value_only MAC

=== Run "summary" command ===
00:00:00:00:00:00 (CRC 0x00 OK)