Adding a probe
Draft. This page describes intended behaviour that has not been verified on a real Gardyn yet.
seedypod reads Atlas Scientific EZO circuits on the Pi’s I²C bus: pH, conductivity (EC) and water temperature (RTD). You add them from the app; there’s no config file to edit and nothing to restart.
1. Wire it
Put the EZO circuit in I²C mode, then connect it to the Pi’s 3.3 V, GND, SDA (GPIO2) and SCL (GPIO3). Each circuit has its own factory address: pH 0x63, EC 0x64, RTD 0x66. Only re-address one if two parts collide.
2. Add it
Open Sensors → Add sensor, pick the probe type, keep the suggested address and press Add. The daemon talks to the circuit first; if it doesn’t answer, nothing is added and you see why (wrong address, loose wire). Once added, the probe’s reading appears under Water quality on the home screen, in Home Assistant, and in the API. It stays added across restarts.
The Sensors screen also lists the built-in parts, and flags any that didn’t respond at startup.
3. Calibrate it
Press Calibrate on the probe’s card and follow the steps; each one shows the live reading so you can wait for it to settle.
| Probe | Steps |
|---|---|
| pH | Midpoint in pH 7.00 buffer (required; clears earlier points), then optionally pH 4.00 and pH 10.00 |
| EC | Dry, in air; then in reference solution (1.413 mS/cm unless yours says otherwise) |
| Water temperature | In water of a known temperature (an ice-water bath is 0 °C) |
Enter the value printed on your solution if it differs from the suggestion. Implausible values are refused before anything reaches the probe. Advanced → Clear wipes the stored calibration.
4. Remove it
Remove on the probe’s card stops its readings and deletes it from Home Assistant; its history is kept. Built-in sensors can’t be removed from the app (the water-level sensor protects the pump).
For developers
GET /api/devices, POST /api/devices/sensors {kind, addr},
DELETE /api/devices/sensors/{kind}/{addr} and
POST /api/sensors/{id}/calibrate. Agents can read the inventory
(list_devices, seedypod://devices) but can’t change it. To support a new
probe type, see ADR-0018.
Sources: ADR 0018: Runtime sensor inventory · hald reference
Imported from docs/SENSORS.md in seedypod/core. Edit it there, not here.