JointBox Controller
Operation Principle
Every JointBox build starts with the Controller. Controller runs ESP32 with firmware of choice like ESPHome, exposes attached extension modules to the Home Assistant, for remote control, and also runs local automations which are completely independent from networking, wireless, or home server availability.
Controller is a central concept in JointBox home automation principles since it gives necessary robustness and connectivity to the build. It uses ESP32 in a form of WEMOS D1 Mini 32 dev board. This lets you easily replace the actual MCU module with no soldering.
Design Features
Controller can be powered by primary (12V DC) power normally fed from a DIN rail mount PSU, and optionally by a battery. The 2x18650 battery can be connected to the separate terminals and is used as an auto-fallback. Controller contains automatic switching circuit which lets it stay powered with no reboot should the mains power interruption happen.
Controller runs a single ESP32 Wemos D1 MCU mini board mounted on board headers. It can be easily pulled out or replaced.
Functionally this module provides: compute, storage, connectivity (WiFi, BLE), power, on-board temperature sensor (ds18b20) to the entire setup.
What's inside
Specifications
| Property | Description |
|---|---|
| Mount | DIN-rail mounted enclosure, 3-unit width (52.5mm) |
| Communication Interfaces | I2C, SPI, UART, 1-Wire, Ethernet RMII, |
| Chip | ESP32 (WEMOS D1 Mini ESP32 devboard) |
| Power | Mains-derived: DC 12V, up to 2A via two-part spring terminals connectors Battery backup: DC 7.4V nominal, 2x18650 batteries via two-part spring terminals connectors |
| 1-Wire | On-board temperature sensor + Interface via 3-pole two-part spring terminals connectors |
| CAN bus | 3-pole 2-part sprint terminal connector for CAN BUS wired interface |
| I2C+Power | 2x module interface: I2C+Power via standard JST 4-pole cable (opposite) |
| SPI | SPI extension interface via standard JST 6-pole cable |
| UART | UART+Power interface via standard JST 4-pole cable |
| Ethernet RMII | 2x7 pole sidecar connector for Ethernet module |
| UI | Separate UI Module interface: I2C+Power via standard JST 4-pole cable, upright |
| Extension Connector | 7-pole side connector for generic extension modules (reserved) |
