Zephyr RTOS on ESP32 — First Steps · Espressif Developer Portal

[giscus[bot]]

Zephyr RTOS on ESP32 — First Steps · Espressif Developer Portal

The developer resources in just one place!

https://developer.espressif.com/blog/zephyr-rtos-on-esp32-first-steps/

[samuelhrqe]

Hello! My name is Samuel Henrique, I’m from Brazil, and I’m trying to learn about Zephyr RTOS on the ESP-WROOM-32 board with 38 pins. I attempted to run the samples/hello_world, built it, and flashed it, but when checking the logs with west espressif monitor, I noticed the board is constantly restarting, showing the following log:

I (49) soc_init: compile time Dec 16 2024 23:06:26
W (49) soc_init: Unicore bootloader
I (50) spi_flash: detected chip: generic
I (54) spi_flash: flash io: dio
I (57) soc_init: chip revision: v1.0
E (60) soc_init: You are using ESP32 chip revision (1) that is unsupported. While it may work, it could cause unexpected behavior or issues.
E (73) soc_init: Proceeding with this ESP32 chip revision is not recommended unless you fully understand the potential risk and limitations.
E (85) soc_init: If you choose to continue, please enable the 'CONFIG_ESP32_USE_UNSUPPORTED_REVISION' in your project configuration.
E (97) boot: HW init failed, aborting
Fatal exception (0): IllegalInstruction
epc1=0x400d13b2, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000
0x400d13b2: abort at /home/samuel/Projetos/zephyr-rtos/zephyr/lib/libc/common/source/stdlib/abort.c:11

I don’t know how to fix this.

I installed Zephyr by following the guide:
https://docs.zephyrproject.org/latest/develop/getting_started/index.html

I tried running the example using this guide:
https://docs.zephyrproject.org/latest/boards/espressif/esp32_devkitc_wroom/doc/index.html

Both results were the same as shown above. Could you please help me?

I'm using the zephyr-sdk-0.17.0 version.

[wmrsouza]

Hi Samuel, thaks for the contact!
You are receiving this warningmessage and probably facing this chash because the ESP32 Rev 1 is not supported on Zephyr. Only ESP32 with chip revisions greater than or equal to Rev 3 are support on Zephyr. If you, despite of the warning message, choose enable CONFIG_ESP32_USE_UNSUPPORTED_REVISION by adding -DCONFIG_ESP32_USE_UNSUPPORTED_REVISION=y to the end of your west build command be aware you can face unexpected behavior while executing your Zephyr application. Enabling theCONFIG_ESP32_USE_UNSUPPORTED_REVISION only inhibits the warning message. To solve the crash you are facing the first recommended measure is continue you tests and studies with a board containing an ESP32 with minimum Rev 3 chip revision.

[samuelhrqe]

Hi Márcio Ribeiro. Thank you for your reply.
After conducting some research and carefully reviewing the log output, I noticed the CONFIG_ESP32_USE_UNSUPPORTED_REVISION=y flag. I added it first to the prj.conf file and then to the board/esp32_devkitc_wroom.conf file. It worked well! This resolved my issue, the warning message and the crash are now gone.

Regarding the chip revision, I was caught by surprise, I had never noticed this while developing with ESP-IDF and FreeRTOS. Although I managed to fix it, I think I’ll need to purchase an ESP32 with a newer revision to avoid potential problems in the future. Thank you very much!