RedVision / TVMS CAN Bridge

Bring a REDARC RedVision / TVMS RV power system into Home Assistant with an ESP32 CAN bridge.

The bridge reads battery, charger, solar, tanks, temperatures, digital inputs and output states. It also sends supported control commands for Manager30, TVMS Rogue and TVMS1280 devices.

Protocol notes are in PROTOCOL.md and RedVision_TVMS_components.dbc.

Hardware

The primary tested hardware is:

• M5Stack Atom Lite
• M5Stack Atomic CAN base using the CA-IS3050G transceiver
• ESPHome and Home Assistant

CAN pins

Signal	Atom pin
CAN TX	GPIO22
CAN RX	GPIO19

REDARC RJ45 pinout

RJ45 pin	Signal
1	CAN 2 L
2	CAN 2 H
3	Ground
4	CAN L
5	CAN H
6	PWRA 12–30V
7	PWRB 12–30V
8	Ground

Do not connect the REDARC supply directly to an ESP32 input. Use a correctly rated and protected regulator or an isolated power design.

Example configuration

external_components:
  - source:
      type: git
      url: https://github.com/dev8edss/Redarc-reverse-engineering
      ref: dev
    refresh: 0s
    components:
      - redarc

redarc:
  canbus:
    tx_pin: GPIO22
    rx_pin: GPIO19
    bit_rate: 250KBPS
    mode: NORMAL

  host_address: 0xFF
  filter_interval: 5s
  history_poll_interval: 60s

  battery_sensor:
    - id: Battery
      source_address: 0x08

  manager:
    - id: Manager30
      source_address: 0x01
      battery_sensor_id: Battery

  redvision_display:
    - id: Redvision1
      source_address: 0x20
    - id: Redvision2
      source_address: 0x21

  tvms_rogue:
    - id: TVMS_Rogue
      source_address: 0x30
      transition_length: 3s

  tvms_1280:
    - id: TVMS1280
      source_address: 0x24

Use NORMAL CAN mode for commands and active requests. LISTENONLY is suitable only for passive monitoring.

Device discovery

REDARC devices periodically broadcast identity DGN 0x1F404. When an ESPHome API client or log viewer connects, the bridge prints the devices it has found:

Discovered devices:
  Device Type         Address       Serial No
  Manager30             1 (0x01)    ...
  BMS Battery Sensor    8 (0x08)    ...
  RedVision Display    32 (0x20)    ...
  TVMS Rogue           48 (0x30)    ...

source_address and host_address accept decimal or hexadecimal values. Two devices cannot use the same source address.

TVMS Rogue output capabilities

All ten Rogue outputs are Home Assistant light entities. The component does not require a YAML list of dimmable outputs.

At startup it requests DGN 0x1FD0E from the Rogue and reads the programmed capability of each output:

• Dimmable output → ESPHome BRIGHTNESS light mode
• Non-dimmable output → ESPHome ON_OFF light mode

The internal command behavior changes immediately:

• Dimmable outputs accept brightness and transition_length.
• Non-dimmable outputs send only ON and OFF commands.
• DGN 0x1FD12 remains the actual hardware level/state feedback source.

Example startup messages:

[I][redarc_tvms_rogue]: Requested Rogue dimming configuration
[I][redarc_tvms_rogue]: Output 2 changed to Dimmable
[I][redarc_tvms_rogue]: Output 10 changed to Dimmable
[I][redarc_tvms_rogue]: Updated 7 Rogue output capabilities; reconnect Home Assistant to refresh light controls

ESPHome changes the runtime light traits and current colour mode immediately. Home Assistant normally refreshes the available brightness controls when its ESPHome API connection reconnects or the integration is reloaded.

Recheck Dimmable Outputs button

Each Rogue creates this diagnostic button:

TVMS Rogue Recheck Dimmable Outputs

Its generated ESPHome ID is:

id(TVMS_Rogue_recheck_dimmable_outputs)

Press it after changing output programming on the RedVision system. The bridge requests 0x1FD0E again, updates every changed runtime capability and logs the changes. Reconnect Home Assistant afterward if a brightness slider needs to be added or removed.

If the request gets no response, ESPHome logs:

[W][redarc_tvms_rogue]: No Rogue dimming configuration response received

No response is expected in LISTENONLY mode because the bridge cannot transmit the request.

Rogue transition settings

transition_length is a Rogue-only setting and belongs inside the tvms_rogue block:

redarc:
  tvms_rogue:
    - id: TVMS_Rogue
      source_address: 0x30
      transition_length: 3s
      true_off_threshold: 1.5

Transitions apply only to outputs discovered as dimmable. During a fade, the component sends changed integer percentages. During fade-out it sends a real OFF command when the level reaches true_off_threshold.

Home Assistant entities

Manager30

• Output current and battery voltage
• Derived device current
• Solar current, voltage, power and energy history
• AC and vehicle input measurements
• Charging mode and charging stage
• CAN date/time and Set Time button

Battery sensor

• Current, voltage, temperature and SOC
• Battery settings and alarm thresholds
• SOC history and calibration actions

TVMS Rogue

• Output 1–10 light entities
• Actual Output 1–10 Level diagnostic sensors
• Input 1–8 diagnostic binary sensors
• Master switch
• Tank 1 and Tank 2
• Input voltage and current
• Output fault/status diagnostic
• Recheck Dimmable Outputs diagnostic button

TVMS1280

• Output 1–10 switches
• Inverter and master switches
• Digital inputs
• Tanks, temperatures and voltage inputs
• Output fault/status diagnostic

Stable ESPHome IDs

An explicit device id: becomes the prefix for generated child IDs:

id(TVMS_Rogue_output_1)
id(TVMS_Rogue_output_1_level).state
id(TVMS_Rogue_input_8).state
id(TVMS_Rogue_recheck_dimmable_outputs).press()
id(TVMS1280_output_1).turn_on()
id(Manager30_solar_power).state

Renaming an entity in Home Assistant does not change its ESPHome compile-time ID.

Development workflow

While testing changes from dev:

1. Keep ref: dev and refresh: 0s.
2. Run Clean Build Files, or clear /data/external_components/*.
3. Validate and compile.
4. Flash the bridge.
5. Check the startup dimming discovery and device-discovery logs.
6. Remove refresh: 0s or use a normal refresh interval afterward.

Troubleshooting

• No control or active configuration request: use CAN NORMAL mode.
• Brightness slider does not match the latest Rogue programming: press Recheck Dimmable Outputs, then reconnect/reload the Home Assistant ESPHome integration.
• No Rogue capability response: confirm the Rogue source_address, bridge host_address, CAN wiring and transmit-capable mode.
• Old YAML option errors or stale behavior: clean ESPHome build files and the external-component cache.
• Dashboard history cards fail: install the ApexCharts Card if the supplied dashboard uses it.

The example dashboard is in RedVision_TVMS_Dashboard.yaml.