Inofficial firmware bakery for Pycom/ESP32 devices

[Andreas]

Introduction

While we are reasonable satisfied in general, some of us are observing random crashes / core panics / Guru meditation errors when unlocking different features of the ESP32. Some of them are well known within the ESP32 and Pycom user communities and Espressif Systems as well as Pycom Limited have been working on different fixes towards mitigating them. So, we are aiming to bring fixes for these issues back to the community by looking a bit under the hood, mainly towards things going on within the Espressif SDK for ESP32 but also beyond.

References

• Investigating random core panics on Pycom/ESP32 devices
• Dragonfly firmware for Pycom/ESP32
• Squirrel firmware for Pycom/ESP32

Download

The download location for these guys is…

https://packages.hiveeyes.org/hiveeyes/foss/pycom/

[Andreas]

About

Recently, we started building and publishing Inofficial firmware images for Pycom devices.
Here, we will give a more detailed overview about what’s inside.

Vanilla

• Index of /hiveeyes/foss/pycom/vanilla/
• Vanilla builds from the Pycom MicroPython “Dev” branch.
• Uses LittleFS.
• Doesn’t include pybytes or other things.
• Provided by @amotl / @andreas on the Pycom user forum.

Notes for 0.1.0-vanilla

• Version 0.1.0-vanilla-standard are the first builds made from the Pycom “Dev” branch, i.e. for 1.20.1.r1.
• Version 0.1.0-vanilla-unicore are moonshot builds having

  #define CONFIG_FREERTOS_UNICORE 1
  

  enabled through "sdkconfig.h".
• For compiling both, xtensa-esp32-elf-gcc (crosstool-NG crosstool-ng-1.22.0-80-g6c4433a) 5.2.0 was used.
• PlatformIO was used to install the Xtensa-ESP32 toolchain like pip install platformio, then platformio platform install espressif32.

Notes for 0.2.0-vanilla

• Version 0.2.0 and up are believed to fix the PSRAM issue in dual core mode, i.e. when both app and pro CPU are enabled. See also PSRAM Cache Issue stills exist (IDFGH-31) #2892 and huge cache coherency issues when both app and pro CPU are enabled.
• For compiling these, xtensa-esp32-elf-gcc (crosstool-NG crosstool-ng-1.22.0-98-g4638c4f) 5.2.0 was used, along the lines with some other changes to newlib.

Notes for 0.3.0-vanilla

• These images are based on the PSRAM-fixes and also add

  #define CONFIG_FREERTOS_UNICORE 1
  

Notes for 0.4.0-vanilla-butterfly

• These builds include the PSRAM-fixes from 0.2.0.
• However, they enable dual-core mode again by stripping #define CONFIG_FREERTOS_UNICORE 1 from sdkconfig.h.
• Issues
  • Investigating random core panics on Pycom/ESP32 devices
  • Investigating core panics with BLE on Pycom devices
• Upgrade to most recent components/esp32/lib and components/bt/lib through their respective release/v3.2 branches, including both of these commits of the precompiled WiFi and Bluetooth drivers:
  • Backport some WiFi fixes 1009 (a756b9c2) · espressif/esp32-wifi-lib@8c893dd · GitHub
  • backports release/v3.3 0903(dd37283) · espressif/esp32-bt-lib@61ccdf0 · GitHub
    fix adv start/stop crash sometimes (e4f2aeac)

Notes for 0.5.0-vanilla-butterfly-csfix

• Same as 0.4.0 but also adding the gist of this commit into the mix.
  fix bug that semaphore may schedule out in Critical Section · espressif/esp-idf@4987a5a · GitHub

Notes for 0.6.0-vanilla-dragonfly

• Fixed some more serious things within some C-level extensions. Now, things feel pretty damn stable both at runtime as well as during provisioning.
• Research: Investigating random core panics on Pycom/ESP32 devices
• Summary: TBD.

Notes for 0.7.0-vanilla-dragonfly-onewire

• Add support for native 1-Wire/DS18X20 driver from Genuine MicroPython, see also Support modonewire from vanilla MicroPython by amotl · Pull Request #356 · pycom/pycom-micropython-sigfox · GitHub.

Notes for 0.8.0-vanilla-squirrel

• Upgrade to Pycom MicroPython 1.20.2.rc3.

Notes for 0.8.1-vanilla-squirrel-ppp

• Add PPP support from Genuine MicroPython
  Add PPP networking to support SIM800 PPPoS implementation by amotl · Pull Request #408 · pycom/pycom-micropython-sigfox · GitHub

Notes for 0.9.0-vanilla-squirrel-ppp-mtime-iuart

• Filesystem metadata fixes
  Fix integer overflow in filesystem stat implementation by amotl · Pull Request #413 · pycom/pycom-micropython-sigfox · GitHub

• UART inverted mode
  mods/machuart.c: Support the UART inverted mode by robert-hh · Pull Request #362 · pycom/pycom-micropython-sigfox · GitHub

Notes for 0.10.0-vanilla-squirrel

• Upgrade to 1.20.2.rc6, see Rc6 by peter-pycom · Pull Request #416 · pycom/pycom-micropython-sigfox · GitHub.

Pybytes

Notes for pybytes-dragonfly and pybytes-squirrel

• Same as the vanilla-dragonfly builds but with VARIANT=PYBYTES enabled.