ESPHome/Homeassistant - Sniff CAN-Bus (MCP2515) from LEDA LUC2

esphome-ledaluc2.yaml

substitutions:
  name: esphome-ledaluc2
  friendly_name: ESPHome LEDA LUC2

esphome:
  name: ${name}
  friendly_name: ${friendly_name}
  min_version: 2023.6.0  # Use a stable ESPHome version for compatibility
  name_add_mac_suffix: false  # Prevent adding MAC suffix to the device name
  project:
    name: esphome.web
    version: dev  # Version of the project

esp32:
  board: esp32dev  # Specify the ESP32 development board
  framework:
    type: arduino  # Use the Arduino framework

# Enable logging for debugging purposes
logger:

# Enable Home Assistant API with encryption key from secrets.yaml
api:
  encryption:
    key: !secret api_key

# Enable over-the-air updates for firmware
ota:
  platform: esphome

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

  # Fallback hotspot in case Wi-Fi connection fails
  ap:
    ssid: "ESPHome-LEDALUC2"
    password: !secret ap_password

# Allow Wi-Fi provisioning via serial connection
improv_serial:

# Enable captive portal for Wi-Fi provisioning via the fallback hotspot
captive_portal:

# Import specific components from an example configuration without overwriting local settings
dashboard_import:
  package_import_url: github://esphome/example-configs/esphome-web/esp32.yaml@main
  import_full_config: false

# Host a simple web server (e.g., for Improv Wi-Fi)
web_server:

# Configure the SPI interface for the MCP2515 CAN bus module
spi:
  clk_pin: GPIO22  # Clock pin
  miso_pin: GPIO17  # Master In Slave Out pin
  mosi_pin: GPIO21  # Master Out Slave In pin

# Configure the CAN bus using the MCP2515 module
canbus:
  - platform: mcp2515
    cs_pin: GPIO16
    can_id: 0x28A
    bit_rate: 125KBPS
    on_frame:
      - can_id: 0x28A
        then:
          - lambda: |-
              // Log all received CAN frames for debugging
              if (x.size() > 0 && x.size() < 8) {
                // Log the received frame data safely
                std::string frame_data;
                for (size_t i = 0; i < x.size(); i++) {
                    char byte_str[5];
                    snprintf(byte_str, sizeof(byte_str), "0x%02X ", x[i]);
                    frame_data += byte_str;
                }

                // Log the frame data in a single line
                ESP_LOGD("CAN", "Received CAN Frame (Size: %d bytes): %s", x.size(), frame_data.c_str());
                
                // Check for specific sizes and log states
                if (x.size() == 2) {
                    ESP_LOGI("CAN", "Interpreted State: Ventilation turned OFF via Display");
                } else if (x.size() == 1) {
                    ESP_LOGI("CAN", "Interpreted State: Ventilation turned ON via Display");
                } else {
                    ESP_LOGW("CAN", "Interpreted State: Unknown or Additional Data");
                }
              } 
              else if (x.size() == 8) {
                uint8_t frame_type = x[0];  // First byte determines the frame type

                // Frame type 0x00: Pressure difference and exhaust temperature
                if (frame_type == 0x00) {
                  // Extract pressure difference from Byte 2
                  float pressure_difference = x[1] * 0.1f;  // Convert to Pascals

                  // Check for adjustment flag in Byte 3
                  if (x[2] == 0x81) {
                    const float PRESSURE_ADJUSTMENT_VALUE = 25.5f;
                    pressure_difference += PRESSURE_ADJUSTMENT_VALUE;
                    ESP_LOGI("CAN", "Adjustment Applied: +%.1f Pa", PRESSURE_ADJUSTMENT_VALUE);
                  }

                  // Extract exhaust temperature from Byte 4
                  float exhaust_temperature = static_cast<float>(x[3]);  // °C

                  // Log decoded values
                  ESP_LOGI("CAN", "Pressure: %.1f Pa, Temperature: %.1f °C", pressure_difference, exhaust_temperature);

                  // Publish to sensors
                  id(pressure_difference_sensor).publish_state(pressure_difference);
                  id(exhaust_temperature_sensor).publish_state(exhaust_temperature);
                }
                // Frame type 0x01: Ventilation status
                else if (frame_type == 0x01) {
                  // Extract ventilation status from Byte 6
                  bool ventilation_active = (x[5] == 0x01);

                  // Log ventilation status
                  ESP_LOGI("CAN", "Ventilation Active: %s", ventilation_active ? "Yes" : "No");
                  ESP_LOGD("CAN", "Ventilation Bytes: Data=%02X %02X %02X %02X %02X %02X %02X %02X",
                          x[0], x[1], x[2], x[3], x[4], x[5], x[6], x[7]);

                  // Publish to binary sensor
                  id(ventilation_status_sensor).publish_state(ventilation_active);
                }
                // Frame type 0x09: Heartbeat signal
                else if (frame_type == 0x09) {
                  // Log loop and counter for reference
                  ESP_LOGD("CAN", "Heartbeat (0x09): Loop=%02X, Counter=%02X", x[2], x[1]);
                }
                // Frame type 0x55: Heartbeat signal
                else if (frame_type == 0x55) {
                  // Log loop and counter for reference
                  ESP_LOGD("CAN", "Heartbeat (0x55): Loop=%02X, Counter=%02X", x[2], x[1]);
                }
                else if (frame_type == 0x80) {
                  ESP_LOGW("CAN", "Error Frame (0x80): Data=%02X %02X %02X %02X %02X %02X %02X %02X",
                          x[0], x[1], x[2], x[3], x[4], x[5], x[6], x[7]);
                }
                else if (frame_type == 0x81) {
                  ESP_LOGW("CAN", "Error Frame (0x81): Data=%02X %02X %02X %02X %02X %02X %02X %02X",
                          x[0], x[1], x[2], x[3], x[4], x[5], x[6], x[7]);
                }
                // Handle unknown frame types
                else {
                  ESP_LOGW("CAN", "Unknown Frame Type. Data=%02X %02X %02X %02X %02X %02X %02X %02X",
                           x[0], x[1], x[2], x[3], x[4], x[5], x[6], x[7]);
                }
              } else {
                ESP_LOGW("CAN", "Unexpected frame size: %d bytes", x.size());
              }

# Define template sensors to hold the values published from the CAN bus data
sensor:
  - platform: template
    name: "Pressure Difference"
    id: pressure_difference_sensor
    unit_of_measurement: "Pa"
    accuracy_decimals: 1
    device_class: pressure  # Device class for pressure sensors
    icon: "mdi:air-filter"  # Optional custom icon for visual clarity
    filters:
      - throttle_average: 3s
   
  - platform: template
    name: "Exhaust Temperature"
    id: exhaust_temperature_sensor
    unit_of_measurement: "°C"
    accuracy_decimals: 1
    device_class: temperature  # Device class for temperature sensors
    icon: "mdi:thermometer"
    filters:
      - throttle_average: 3s
          

binary_sensor:
  - platform: template
    name: "Ventilation Status"
    id: ventilation_status_sensor
    device_class: running  # Device class for indicating system activity
    icon: "mdi:fan"  # Optional custom icon for ventilation

Hi, ich bin nach der Anleitung vorgegangen, bekomme aber keine Werte angezeigt. Anscheinend werden keine CAN-Frames empfangen, weil auch nichts geloggt wird.
Plus- und Minuspol waren bei mir genau andersrum, als auf dem Bild. Evtl sind die CAN Pins dann auch andere? Evtl kann mir ja jemand weiterhelfen ...
Vielen Dank im Voraus!

Hi, ich bin nach der Anleitung vorgegangen, bekomme aber keine Werte angezeigt. Anscheinend werden keine CAN-Frames empfangen, weil auch nichts geloggt wird. Plus- und Minuspol waren bei mir genau andersrum, als auf dem Bild. Evtl sind die CAN Pins dann auch andere? Evtl kann mir ja jemand weiterhelfen ... Vielen Dank im Voraus!

Hi @Hooorny - du hast Recht, im Bild waren die Kabel vertauscht. Die musst du korrekt anstecken. So sieht die Korrekte Verkabelung aus:

Hey, irgendwie bin ich zu doof das Zeug zusammen zu löten. Könnte mir jemand, natürlich gegen Aufwandsentschädigung, so ein Ding zusammen bauen?

Hallo, ich habe eine 30-Pin-ESP32 hier. Kann mir bitte jemand die PIN-Belegung dafür zum MCP2525 nennen? Muss ich im Code dann Änderungen vornehmen?
Danke!