ESP32-C3 Support

[aptonline]

I have a number of ESP32-C3 devices and happy to test and confirm support for espectre. Looking at the code what would I need to change to test?

Thanks

[francescopace]

Hi @aptonline,

Thanks for offering to test! ESP32-C3 support should work with minimal changes since it uses the same legacy CSI API as ESP32-S3.

For ESPHome (ESPectre 2.0):

1. Create a new espectre-c3.yaml

esphome:
  name: espectre-c3

esp32:
  variant: ESP32C3 
  partitions: partitions.csv
  framework:
    type: esp-idf
    version: 5.5.1
    sdkconfig_options: 
      CONFIG_PM_ENABLE: n
      CONFIG_ESP_WIFI_STA_DISCONNECTED_PM_ENABLE: n
      CONFIG_ESP_WIFI_CSI_ENABLED: y 

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

api:

ota:
  - platform: esphome

logger:
  level: INFO

external_components:
  - source:
      type: local
      path: components
    components: [ espectre ]

# ESPectre - WiFi CSI Motion Detection
espectre:
  traffic_generator_rate: 100
  segmentation_threshold: 1.0
  segmentation_window_size: 50
  hampel_enabled: true

2. Prepare your environment following SETUP instructions.

3. Compile and flash - the CSI component should work out of the box since C3 shares the same CSI structure as S3.

esphome run espectre-c3.yaml

What to watch for:

• ESP32-C3 is single-core (like C6), so timing-sensitive operations may behave differently than on dual-core S3
• Memory is more constrained (~400KB SRAM vs 512KB on S3)
• No PSRAM support

If you can test and report back, I'd be happy to add official C3 support. Let me know if you run into any issues!

[francescopace]

Hi @aptonline! I just added experimental support for the ESP32-C3 (and other ESP32 variants).

How to test

1. Download the new C3 configuration:

curl -O https://raw.githubusercontent.com/francescopace/espectre/main/examples/espectre-c3.yaml

2. Edit WiFi credentials in the file

3. Flash:

esphome run espectre-c3.yaml

What was changed

The code now properly detects the ESP32-C3 and uses the legacy CSI API (same structure as ESP32-S3):

#elif CONFIG_IDF_TARGET_ESP32C3
  // ESP32-C3 configuration (RISC-V, similar structure to S3)
  wifi_csi_config_t csi_config = {
    .lltf_en = false,
    .htltf_en = true,
    .stbc_htltf2_en = false,
    .ltf_merge_en = false,
    .channel_filter_en = false,
    .manu_scale = true,
    .shift = 4,
  };

Please report back!

Since you have multiple ESP32-C3 devices, your testing would be super valuable. Please let us know:

• ✅ Does it compile and flash successfully?
• ✅ Does the NBVI calibration complete?
• ✅ Does motion detection work?
• 📊 How does accuracy compare to C6/S3?

Looking forward to your feedback! 🙏

[bjesus]

Confirming that it seems to work fine. I cannot compare because I don't have the other devices

[francescopace]

Confirming that it seems to work fine. I cannot compare because I don't have the other devices

Thank you so much @bjesus !

[aptonline]

Hi, just seen the comments. Happy to test and report back in the next few days. Thanks.

[WLaoDuo]

Thanks @francescopace 🎉 !
on my board<airm2m_core_esp32c3>

1. compile and flash successfully✅
2. NBVI calibration seems successed. ✅
3. motion detection work well ! ✅
4. I only have one board of esp32c3

esphome:
  name: espectre
  platformio_options:
    board_build.flash_mode: dio #only for <airm2m_core_esp32c3> board to flash ,simple board not need this line code
    board_build.mcu: esp32c3

esp32:
  board: airm2m_core_esp32c3 #esp32-c3-devkitm-1
  variant: esp32c3
  framework:
    type: esp-idf
    version: 5.5.1
    sdkconfig_options:
      # Power Management (critical for CSI reliability)
      CONFIG_PM_ENABLE: n                             # Disable all power management
      CONFIG_ESP_WIFI_STA_DISCONNECTED_PM_ENABLE: n   # No power save when disconnected
      # CSI Feature
      CONFIG_ESP_WIFI_CSI_ENABLED: y                  # Enable CSI extraction from WiFi packets

wifi:
  networks:
  -  ssid: !secret wifi_ssid
     password: !secret wifi_password
  manual_ip:
    static_ip: 192.168.31.58
    gateway: 192.168.31.1
    subnet: 255.255.255.0
  ap:
    ssid: "Espectre-Fallback"
    password: "fallback_pass"
  on_connect:
    - logger.log: "WiFi connect!"
  on_disconnect:
    - logger.log: "WiFi failed!"
web_server:
  port: 80

# Load ESPectre component from GitHub
external_components:
  - source:
      type: git
      url: https://github.com/francescopace/espectre
      ref: main
    components: [ espectre ]
    refresh: always

# ESPectre - WiFi CSI Motion Detection
espectre:
  traffic_generator_rate: 100
  segmentation_threshold: 1.0
  segmentation_window_size: 50
  hampel_enabled: true

# Enable logging
logger:
  baud_rate: 115200
  hardware_uart: UART0
  level: INFO
# Enable API for Home Assistant
#api:

# Enable OTA updates via ESPHome
ota:
  - platform: esphome

[francescopace]

@WLaoDuo super cool! Thank you so much

[aptonline]

@WLaoDuo using your config flashed ok and seems to work but the motion is never triggering even when I set the threshold to really low.

[WLaoDuo]

@WLaoDuo using your config flashed ok and seems to work but the motion is never triggering even when I set the threshold to really low.

@aptonline My config is only tested on <airm2m_core_esp32c3> board, on other board maybe not work well , could we see ur code and log?

[aptonline]

Sorry for the delay in testing and getting back to you, yes I can also confirm everything working as expected from my brief testing. Many thanks for implementing support :)

[mvfc]

@francescopace It also works with the C3 super mini if you set the traffic generator rate to less than or equal 94. If you put 95 or more, it takes an hour and 30 minutes to calibrate and then it doesn’t work properly. I’ve tested on three different AliExpress and Temu boards. As long as you put the limit on the traffic generator rate, it works flawlessly. Some cheaper clones may not support QIO so you’d have to set the platformio build mode to DIO

[francescopace]

Thank you so much @mvfc for this valuable feedback! 🙏
I've updated the documentation and C3 YAML example with your findings:

• traffic_generator_rate: 94 as safe default for Super Mini boards
• Added DIO flash mode option for clones that don't support QIO
• New troubleshooting section in SETUP.md specific to C3 Super Mini
• Removed the "EXPERIMENTAL" warning - C3 is now officially tested by the community!

See commit a302abc

Your testing on multiple boards from AliExpress/Temu is exactly the kind of feedback that makes the project truly open source.
Super Mini boards are super cheap and popular, so these notes will help many users.
I noticed you had opened a PR (#45) and then closed it - feel free to reopen it or open new ones in the future, so you can be marked as contributor from Github!

Fra

[tbrasser]

Flashing on all my Shelly Mini1 Gen3's. (also C3's?) They also run bluetooth_proxy for bermuda.

All seems to work 👍

[jovanmij]

can you share your config to get both bluetooth_proxy and espectre?