WiCAN ESPHome Configuration (work in progress, abbreviated)

esphome.yaml

# Be warned: This is just a first try and still very much work in progress - no guarantees given whatsoever!
#
# To install the ESPHome firmware on the WiCAN for the first time (before being able to use ESPHome OTA), I built the firmware
# for download (in "modern" format) and then used the following command line on Linux:
# esptool.py --before=default_reset --after=hard_reset --no-stub write_flash --flash_mode dio --flash_freq 80m --flash_size 4MB 0x0 /home/.../Downloads/m-wican-factory.bin
#
# Don't forget to short the pins to enable boot mode (https://github.com/meatpiHQ/wican-fw#obd).
#
# Using the graphical tool (https://github.com/meatpiHQ/wican-fw#2-usb-flash) will probably work just as well. Just populate
# the first item in the list with 0x0 and /home/.../Downloads/m-wican-factory.bin and leave the rest empty.
#
# Thereafter I just used the ESPHome OTA feature - but be aware that WiFi must be turned on for this to work, i.e. the power
# safe mode (see below) must be off.

substitutions:
  device_name: m-eup-wican

esp32:
  variant: ESP32C3
  board: esp32-c3-devkitm-1

esphome:
  name: ${device_name}

logger:

api:

time:
  platform: homeassistant

web_server:
  version: 2
  ota: false
  include_internal: true

wifi:
  # your details here

ota:
  password: # your details here


packages:

  leds:

    output:

      - id: blue_led_output
        platform: gpio
        pin: 7

      - id: green_led_output
        platform: gpio
        pin: {number: 8, inverted: true}

      - id: yellow_led_output
        platform: gpio
        pin: {number: 9, inverted: true}


    light:

      - platform: binary
        id: blue_led
        output: blue_led_output

      - platform: binary
        id: green_led
        output: green_led_output

      - platform: binary
        id: yellow_led
        output: yellow_led_output


  can:

    canbus:

      - platform: esp32_can
        tx_pin: 0
        rx_pin: 3
        bit_rate: 500kbps
        can_id: 0 # mandatory but we do not use it
        on_frame:
          # dump all frames to log
          - can_id: 0
            can_id_mask: 0
            then:
              - lambda: |-
                  auto data_pretty = remote_transmission_request ? "n/a" : format_hex_pretty(x).c_str();
                  ESP_LOGD("eup_dump", "can_id: 0x%08x, rtr: %d, length: %d, content: %s", can_id, remote_transmission_request, x.size(), data_pretty);
          # first byte: real data length
          - can_id: 0x7ED # VWUP_BAT_MGMT_RX
            then:
              - lambda: |-
                  // VW e-Up absolute SOC from Battery Management (available during "vehicle on" and "vehicle charging")
                  if (x.size() >= 5 && x[0] >= 4 && x[1] == 98 && x[2] == 0x02 && x[3] == 0x8C) // VWUP_BAT_MGMT_SOC_ABS
                    // https://github.com/openvehicles/Open-Vehicle-Monitoring-System-3/blob/9ddbb0182158d8d7d4afe03dce61afb2ec856787/vehicle/OVMS.V3/components/vehicle_vweup/src/vweup_obd.cpp#L850
                    id(car_soc).publish_state(round(2.0f * x[4] * 100 / 250) / 2.0f); // round to 0.5 %

    switch:

      - platform: gpio
        id: can_enabled
        pin:
          number: 6
          inverted: true
        restore_mode: ALWAYS_ON
        # TBD: disabling CAN seems to disturb the driver badly and it will not work again after enabling again but only after reboot
        # on_turn_on:
        #   - lambda: twai_start();
        # on_turn_off:
        #   - lambda: twai_stop(); # keep driver error counter low

    script:

      # Poll PIDs
      # first byte: data length
      # second byte 0x22: VEHICLE_POLL_TYPE_READDATA / ReadDataByIdentifier (16 bit PID)
      # needs to be filled up with 0xAA to be accepted by the control units
      - id: query_soc_script
        then:
          - if:
              condition: {switch.is_on: can_enabled}
              then:
                # VW e-Up SOC from Battery Management (available during "vehicle on" and "vehicle charging")
                # based on https://github.com/openvehicles/Open-Vehicle-Monitoring-System-3/blob/9ddbb0182158d8d7d4afe03dce61afb2ec856787/vehicle/OVMS.V3/components/vehicle_vweup/src/vweup_obd.cpp#L67
                # also see "xvu.b.soc" here: https://docs.openvehicles.com/en/latest/components/vehicle_vweup/docs/index_obd.html#custom-metrics
                - canbus.send:
                    can_id: 0x7E5 # VWUP_BAT_MGMT_TX
                    data: [ 3, 0x22, 0x02, 0x8C, 0xAA, 0xAA, 0xAA, 0xAA ] # VWUP_BAT_MGMT_SOC_ABS

    interval:
      - interval: 1min
        then:
          - script.execute: query_soc_script

    sensor:

      - platform: template
        id: car_soc
        name: '${device_name} car_soc'
        unit_of_measurement: '%'
        accuracy_decimals: 1
        device_class: battery
        state_class: measurement


  power_safe_mode:

    sensor:

      - platform: adc
        id: starter_battery_voltage
        name: '${device_name} starter_battery_voltage'
        pin: 4
        attenuation: 11db # https://github.com/meatpiHQ/wican-fw/blob/bf212132f8e506f2c520e917daf86e53a1070302/main/sleep_mode.c#L234
        filters:
          - lambda: return x * 116 / 16; # https://github.com/meatpiHQ/wican-fw/blob/bf212132f8e506f2c520e917daf86e53a1070302/main/sleep_mode.c#L397
        update_interval: 5s
        unit_of_measurement: V
        accuracy_decimals: 1
        device_class: voltage
        state_class: measurement

    binary_sensor:

      - platform: template
        id: car_is_on
        name: '${device_name} car_is_on'
        lambda: return id(starter_battery_voltage).state >= 12.9;
        # did not find any other way to realize different timeouts for on and off :-(
        # neither delay_on and delay_off nor on_state with delays based on state did work reliably
        on_state:
          - script.execute: power_safe_mode_script

    script:

      - id: power_safe_mode_script
        mode: restart # important, otherwise delays will not cancel each other
        then:
          - if:
              condition: {binary_sensor.is_on: car_is_on}
              then:
                - delay: 10sec
                - switch.turn_off: power_safe_mode
              else:
                - delay: 3min
                - switch.turn_on: power_safe_mode

    switch:

      - platform: template
        id: power_safe_mode
        name: '${device_name} power_safe_mode'
        optimistic: true
        restore_mode: ALWAYS_OFF
        on_turn_on:
          - logger.log: "Power Safe Mode: ON"
          - delay: 3sec # allow to send the latest state to HA before disconnecting wifi
          # - switch.turn_off: can_enabled
          - wifi.disable:
        on_turn_off:
          - logger.log: "Power Safe Mode: OFF"
          - wifi.enable:
          # - switch.turn_on: can_enabled
          - delay: 10sec
          - script.execute: query_soc_script


    api:
      # Required for wifi.disable to not trigger a reboot. We probably need to keep an eye on this to ensure that it really
      # is not required. A potential workaround could be to just trigger a reboot when resuming from power safe mode.
      # This would also have the advantage of not having to disable and again re-enable the CAN bus for sleeping.
      reboot_timeout: 0s

@jaripetteri Sorry, but I only have an e-Up that does not have a car alarm system.

@felixstorm No problem, I'll try to disable sending when car is locked or something. It may be something else also.

I'm looking OVMS code but can't figure out how you end up on this data:
data: [ 3, 34, 2, 140, 170, 170, 170, 170 ]

2, 140 is VWUP_BAT_MGMT_SOC_ABS 0x028C but where the rest is coming? I'll try to add some more sensors there.
like VWUP_BAT_MGMT_ODOMETER 0x02BD and
data: [ 3, 34, 2, 189, 170, 170, 170, 170 ]
but not sure is that correct.

Is 170 = 0xAA as empty? What it 3, 34?

I'm by the way using simple es32-c3 super mini board with can-bus chip and can get SoC with that about 10€ device. Now building device based on esp32-wrover dev kit to run OVMS there. Let's see where that end ups.

@jaripetteri I added some comments in the gist above and switched some values to hex - this way it should be more obvious where the constants etc. come from.