The Protocol Wizard helps you build your home assistant devices without need for any yaml!
Configure and control devices entirely from the UI — no YAML, no restarts!
Protocol Wizard lets you discover, test, and integrate devices (Modbus, SNMP) directly in Home Assistant — all through a simple, powerful interface.
All run-time!
Add and configure sensors at runtime — no reboots required
Work in progress — actively developed and improving!
- Zero YAML configuration — everything done via the Home Assistant UI
- Device templates support! Just present your device as a json template! (see below)
- Full support for serial (RS485/USB) and IP-based (TCP & UDP)
- Runtime entity management — add, edit, or remove sensors without restarting HA
- Dedicated Lovelace cards for live reading/writing any register/OID/etc. (perfect for testing and debugging)
- Create only the entities you need — keep your setup clean and efficient
- Modbus: Multiple slaves supported (up to 255 per bus/network) with individual slave IDs
- Modbus: Multiple masters possible (HA as master; coexists with other masters if no conflicts)
- Configurable refresh intervals per device
- Full automation support — use sensors in automations, scripts, and dashboards
- Advanced options: scaling, offset, byte/word order, endianness, bit handling, and more
Probe and control any register in real-time with the included card
Once available in HACS default repository, install with one click.
- Go to HACS → Integrations → ⋮ → Custom repositories
- Add repository:
URL:https://github.com/partach/protocol_wizard
Category: Integration - Click Add
- Search for "Protocol Wizard" and install
- Restart Home Assistant
- Go to Settings → Devices & Services → + Add Integration → Search for Protocol Wizard
The included Lovelace card is automatically registered on startup.
A browser refresh may be needed the first time to see it.
For reliable serial Modbus (RS485), install 120Ω termination resistors at both ends of the bus only.
Too many resistors degrade the signal; none can cause reflections and errors.
how to apply the 120 ohm resistor with multiple devices attached on the bus
- Click + Add Integration → Choose Protoco Wizard
- Select Modbus / SNMP / etc.
Add and configure sensors at runtime — no reboots required
- Select connection type: Serial or IP (TCP/UDP)
- Enter:
- Slave ID (usually 1)
- A test register address (often 0 or 30001 → use 0 in the integration)
- Test register size (usually 1 or 2)
- Provide connection details (port, baudrate, host, etc.)
- The integration will auto-test connectivity
→ Success? You're ready!
Simple device setup
Add the Protocol Wizard Card to a dashboard:
- Edit dashboard → Add card → Search for "Protocol Wizard Card"
- Select your device
Now you can:
- Read any register instantly
- Write values to test device behavior
- Experiment with data types, byte order, and scaling
Perfect for reverse-engineering undocumented devices!
Once you know which registers you want:
- Go to your Protocol Wizard device → Configure → Add register
- Fill in name, address, data type, unit, scaling, etc.
- Advanced options available (click "Show advanced options")
Full control over sensor configuration
Your new sensors appear immediately — no restart needed.
You can later edit or delete them from the same options menu.
Via the hub configuration (gear symbol) you can read device templates (in standard JSON format). These are easy to make (AI can be your friend) and help you import your device (or change) run-time with a few clicks. SDM630 basic profile is provided in the code. Just feed this to Grok, ChatGPT, Claude, etc. And ask to get this for device X/Y. Then add to the template directory of the integration `/custom_components/protocol_wizard/templates/mydevicename.json Also send them to me so i can possibly add them for a next release :)
The Format (entry per register)
[
{
"name": "Phase 1 Voltage",
"address": 0,
"data_type": "float32",
"register_type": "input",
"rw": "read",
"unit": "V",
"scale": 1.0,
"offset": 0.0,
"byte_order": "big",
"word_order": "big",
"allow_bits": false
}
]
SNMP example
[
{
"name": "System Description",
"address": "1.3.6.1.2.1.1.1.0",
"data_type": "string",
"read_mode": "get"
},
{
"name": "System Uptime",
"address": "1.3.6.1.2.1.1.3.0",
"data_type": "integer",
"read_mode": "get"
},
{
"name": "System Name",
"address": "1.3.6.1.2.1.1.5.0",
"data_type": "string",
"read_mode": "get"
},
{
"name": "Interface Speeds",
"address": "1.3.6.1.2.1.2.2.1.5",
"read_mode": "walk"
}
]
When adding or editing a register, the following fields are available:
| Field | Required | Default | Description |
|---|---|---|---|
| name | Yes | - | Human-readable name for the entity |
| address | Yes | - | Modbus register address (0–65535) |
| data_type | Yes | uint16 |
How to decode the value: uint16, int16, uint32, int32, float32, uint64, int64 |
| register_type | Yes | input |
Function code: auto, holding, input, coil, discrete |
| rw | Yes | read |
Entity type: read (sensor), write (number), rw (both) |
| unit | No | - | Unit of measurement (e.g., "V", "A", "W") |
| scale | No | 1.0 |
Multiplier applied after decoding (value × scale + offset) |
| offset | No | 0.0 |
Additive offset after scaling |
| options | No | - | JSON mapping for select entity (e.g., {"0": "Off", "1": "On"}) |
| byte_order | No | big |
Byte order within each word (big/little) |
| word_order | No | big |
Order of the 16-bit words (big/little) for multi-register values |
| format | No | - | python formating for read values like {d}d {h}h {m}m for seconds to human readible value |
| min | No | - | Minimum value for writeable number entities |
| max | No | - | Maximum value for writeable number entities |
| step | No | 1.0 |
Step size for number entity adjustments |
- Voltages/Currents:
data_type = "uint16",scale = 0.1or0.01, unit "V"/"A" - Power: Often
uint32orfloat32with appropriate scaling - Status bits: Use
coil/discrete+optionsJSON for friendly names
- No more YAML hell — perfect for devices with poor documentation
- Fast iteration — test registers live, then save only what you need
- Beginner-friendly yet powerful for advanced users
- Full control — bit-level access, custom scaling, endianness, raw mode
- Templates for common devices: Pre-load register sets for popular boards like WaveShare RS485 series (save typing, reduce errors)
- Enhanced card display: HEX, ASCII, and bitwise views for raw register data
- Diagnostic export: One-click YAML/JSON report of all registers and values for troubleshooting
This integration is under active development. Found a bug? Have a feature request?
→ Open an issue on GitHub: https://github.com/partach/protocol_wizard/issues
Contributions welcome!
Join the conversation: GitHub Discussions
See CHANGELOG.md
If you find Protocol Wizard useful, consider buying me a coffee! ☕
Made with ❤️ for the Home Assistant community