esp_image: Checksum failed. Started Happening on power up, no firmware change.

[jtmopti]

Hello,

I have a device using ESP32 C3 module. The device had been operating fine for a and then started to now power up with boot loop caused by `esp_image: Checksum failed.` There was no ota update done before this time, or actually ever on these specific devices. They were programmed straight from a wired UART connection.

I can also not connect to the chip to dump this partition or try reprogramming. This has happened to 10 units. What could cause this failure mode?

Logs are as follows:

Code: Select all

ESP-ROM:esp32c3-api1-20210207
Build:Feb  7 2021
rst:0x3 (RTC_SW_SYS_RST),boot:0xf (SPI_FAST_FLASH_BOOT)
Saved PC:0x403cfcc4
SPIWP:0xee
mode:DIO, clock div:1
load:0x3fcd5820,len:0x133c
load:0x403cc710,len:0x93c
load:0x403ce710,len:0x2df0
entry 0x403cc710
 (35) boot: ESP-IDF v5.0.1 2nd stage bootloader[0m
 (35) boot: compile time 05:34:53[0m
 (35) boot: chip revision: v0.3[0m
(37) boot.esp32c3: SPI Speed      : 80MHz[0m
 (42) boot.esp32c3: SPI Mode       : DIO[0m
 (46) boot.esp32c3: SPI Flash Size : 4MB[0m
 (51) boot: Enabling RNG early entropy source...
 (57) boot: Partition Table:
 (60) boot: ## Label            Usage          Type ST Offset   Length
 (67) boot:  0 nvs              WiFi data        01 02 00009000 00012000
 (75) boot:  1 otadata          OTA data         01 00 0001b000 00002000
 (82) boot:  2 phy_init         RF data          01 01 0001d000 00001000
 (90) boot:  3 ota_0            OTA app          00 10 00020000 00100000
 (97) boot:  4 ota_1            OTA app          00 11 00120000 00100000
(105) boot:  5 data1       Unknown data     01 a0 00220000 00019000
 (112) boot:  6 data2      Unknown data     01 a0 00239000 00019000
 (120) boot:  7 coredump         Unknown data     01 03 00252000 00010000
 (127) boot:  8 iddata           WiFi data        01 02 00262000 00003000
 (135) boot: End of partition table
 (139) esp_image: segment 0: paddr=00020020 vaddr=3c080020 size=17420h ( 95264) map
 (162) esp_image: segment 1: paddr=00037448 vaddr=3fc92600 size=03a88h ( 14984) load
 (165) esp_image: segment 2: paddr=0003aed8 vaddr=40380000 size=05140h ( 20800) load
 (172) esp_image: segment 3: paddr=00040020 vaddr=42000020 size=728cch (469196) map
 (247) esp_image: segment 4: paddr=000b28f4 vaddr=40385140 size=0d3ech ( 54252) load
 (257) esp_image: Checksum failed. Calculated 0xf read 0xd
 (257) boot: OTA app partition slot 0 is not bootable
 (258) esp_image: image at 0x120000 has invalid magic byte (nothing flashed here?)
 (266) boot: OTA app partition slot 1 is not bootable
 (272) boot: No bootable app partitions in the partition table
ESP-ROM:esp32c3-api1-20210207
Build:Feb  7 2021
rst:0x3 (RTC_SW_SYS_RST),boot:0xf (SPI_FAST_FLASH_BOOT)
Saved PC:0x403cfcc4

This log repeats over and over.

[jtmopti]

I have done some more digging on this issue and found that in every device I have been able to check there is a single bit in program memory flipped from 1->0.

This device does have an unstable power supply and can get repeated brownouts at startup, but we have a 2.9V voltage supervisor on the enable pin which should prevent this from being a problem.