不用到現場，也能做出 Remote HMI

1. 01

   在現場錄製通訊 log

   將 Falcon 串接在 PLC 與 HMI 之間，呼叫 log.record 錄下一個班次的實際操作。所有點位讀寫都會以 JSON-RPC 格式保存。

2. 02

   在辦公室回放

   把 log 帶回辦公室，呼叫 log.replay。Falcon 會依原始時序把通訊重新發佈到 MQTT，就像產線正在運轉。

   // Topic: falcon/line-01/rpc/req
   {
     "jsonrpc": "2.0",
     "id": "replay-01",
     "method": "log.replay",
     "params": { "log": "2026-11-03_line01_shift-a", "speed": 1.0, "loop": true }
   }

3. 03

   交給 AI Agent 開發

   把需求交給 AI coding agent。Agent 會自己訂閱回放資料、整理點位、撰寫 PySide6 程式並執行測試，有錯就自動修正。

   Build a PySide6 window for "Line 01 Press".
   Data arrives as JSON-RPC notifications on MQTT topic
   falcon/line-01/event, method "traffic.observed", params.tags.
   - Show D100 (pressure, bar) as a large gauge-style number
   - Show M20 (motor running) as a green/grey status lamp
   - "Set pressure" spin box sends JSON-RPC "tag.write" for D100
     to falcon/line-01/rpc/req
   Use paho-mqtt in a QThread and Qt signals to update the UI.

4. 04

   對著回放資料驗證

   執行產生的程式，介面會即時反映回放資料。調整版面、警報與數值格式，直到符合操作人員需求。

   import json, sys, uuid
   import paho.mqtt.client as mqtt
   from PySide6.QtCore import QObject, Signal
   from PySide6.QtWidgets import (QApplication, QLabel, QPushButton,
                                  QSpinBox, QVBoxLayout, QWidget)
   
   GW = "falcon/line-01"
   
   class Bus(QObject):
       tags = Signal(dict)
   
       def __init__(self):
           super().__init__()
           self.c = mqtt.Client(mqtt.CallbackAPIVersion.VERSION2)
           self.c.on_message = lambda c, u, m: self.tags.emit(
               json.loads(m.payload)["params"]["tags"])
           self.c.connect("broker.local", 1883)
           self.c.subscribe(f"{GW}/event")
           self.c.loop_start()
   
       def write(self, tag, value):
           self.c.publish(f"{GW}/rpc/req", json.dumps({
               "jsonrpc": "2.0", "id": str(uuid.uuid4()),
               "method": "tag.write", "params": {"tag": tag, "value": value}}))
   
   app = QApplication(sys.argv)
   bus, win = Bus(), QWidget()
   pressure, motor = QLabel("--"), QLabel("MOTOR")
   setpoint, apply = QSpinBox(maximum=5000), QPushButton("Set pressure")
   apply.clicked.connect(lambda: bus.write("D100", setpoint.value()))
   
   def update(tags):
       if "D100" in tags: pressure.setText(f"{tags['D100']} bar")
       if "M20" in tags:
           motor.setStyleSheet(f"background:{'#2e7d32' if tags['M20'] else '#555'}")
   
   bus.tags.connect(update)
   layout = QVBoxLayout(win)
   for w in (pressure, motor, setpoint, apply): layout.addWidget(w)
   win.setWindowTitle("Line 01 — Remote HMI"); win.show()
   sys.exit(app.exec())

5. 05

   切換到實機上線

   把 MQTT 連線改成現場 Broker，Remote HMI 即可監看真實產線；開啟授權後，也能透過 tag.write 進行控制介入。

範例中的 Topic、方法與點位名稱為示意，請依實際產品文件與現場點位調整。