Modbus TCP データ収集と可視化

Python Modbus TCP simulator
     127.0.0.1:1502
            ↓
     reComputer RK3576
            ↓
 Home Assistant Container
            ↓
 Live temperature/humidity / history graphs

python3 --version
sudo docker ps --filter name=homeassistant
sudo docker inspect homeassistant --format '{{.HostConfig.NetworkMode}}'

cat > ~/modbus_demo.py <<'PY'
import math
import socketserver
import struct
import time


class ModbusHandler(socketserver.BaseRequestHandler):
    def read_exact(self, size):
        data = b""
        while len(data) < size:
            chunk = self.request.recv(size - len(data))
            if not chunk:
                return None
            data += chunk
        return data

    def handle(self):
        try:
            while True:
                header = self.read_exact(7)
                if not header:
                    break

                tid, pid, length, unit = struct.unpack(">HHHB", header)
                if pid != 0 or not 2 <= length <= 254:
                    break

                request = self.read_exact(length - 1)
                if not request:
                    break

                function = request[0]
                if function == 3 and len(request) == 5:
                    address, count = struct.unpack(">HH", request[1:])

                    if count < 1 or count > 2 or address + count > 2:
                        response = bytes([0x83, 2])
                    else:
                        temperature = round(
                            (25 + 2 * math.sin(time.monotonic() / 20)) * 10
                        )
                        humidity = round(
                            (60 + 10 * math.sin(time.monotonic() / 30)) * 10
                        )
                        registers = [temperature, humidity]
                        response = bytes([3, count * 2]) + b"".join(
                            struct.pack(">H", value)
                            for value in registers[address:address + count]
                        )
                else:
                    response = bytes([function | 0x80, 1])

                reply = struct.pack(">HHHB", tid, 0, len(response) + 1, unit) + response
                self.request.sendall(reply)
        except (OSError, ConnectionError):
            pass


class ModbusServer(socketserver.ThreadingTCPServer):
    allow_reuse_address = True
    daemon_threads = True


with ModbusServer(("127.0.0.1", 1502), ModbusHandler) as server:
    print("Modbus TCP server running at 127.0.0.1:1502", flush=True)
    server.serve_forever()
PY

nohup python3 ~/modbus_demo.py > ~/modbus_demo.log 2>&1 &

ss -lntp | grep ':1502'
cat ~/modbus_demo.log

Modbus TCP server running at 127.0.0.1:1502

sudo cp ~/homeassistant/config/configuration.yaml \
  ~/homeassistant/config/configuration.yaml.bak

sudo nano ~/homeassistant/config/configuration.yaml

modbus:
  - name: rk3576_demo
    type: tcp
    host: 127.0.0.1
    port: 1502

    sensors:
      - name: RK3576 Room Temperature
        unique_id: rk3576_demo_temperature
        slave: 1
        address: 0
        input_type: holding
        data_type: uint16
        scale: 0.1
        precision: 1
        unit_of_measurement: "°C"
        device_class: temperature
        state_class: measurement
        scan_interval: 5

      - name: RK3576 Room Humidity
        unique_id: rk3576_demo_humidity
        slave: 1
        address: 1
        input_type: holding
        data_type: uint16
        scale: 0.1
        precision: 1
        unit_of_measurement: "%"
        device_class: humidity
        state_class: measurement
        scan_interval: 5

sudo docker exec homeassistant \
  python -m homeassistant --script check_config --config /config

sudo docker restart homeassistant

http://<RK3576_IP>:8123