Proof of Concept (PoC) Objective: Integrate a heat pump (Modbus RS485 communication) with a ThingsBoard Cloud instance (free tier). -Read: 3 specific Modbus registers (addresses/codes provided). -Write: RPC command from ThingsBoard to set temperature setpoint on the heat pump. Provided Setup: -Heat pump with Modbus RS485 interface. -RS485-to-MQTT gateway: PUSR W610 (IP access via Tailscale VPN). -ThingsBoard Cloud instance (full access shared). -Raspberry Pi on the same network (for RS485 simulation/remote testing if needed). Expected Deliverables: -MQTT gateway config → ThingsBoard integration (widgets displaying 3 values). -Functional RPC writeback (temp setpoint from dashboard). -Documentation (schematics, config files, test results). -Live demo via Tailscale.