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我正在使用pymodbus库来创建 Modbus 服务器。我发现了您可以在此处找到的所有示例。我遇到了与在服务器（从）端写入浮点值相关的问题。有一个updating_writer函数，我想将浮点值 =22.34写入 2 个保持电阻：

...
    def updating_writer(a):
        context  = a[0]
        register = 3
        slave_id = 0x00
        address  = 0x0
        builder = BinaryPayloadBuilder(endian=Endian.Little)
        builder.add_32bit_float(22.34)
        res = builder.build()
        context[slave_id].setValues(register, address, res)

    store = ModbusSlaveContext(
        di = ModbusSequentialDataBlock(0, [17]*100),
        co = ModbusSequentialDataBlock(0, [17]*100),
        hr = ModbusSequentialDataBlock(0, [17]*100),
        ir = ModbusSequentialDataBlock(0, [17]*100))
    context = ModbusServerContext(slaves=store, single=True)
...

但是，当我从 Modbus 主设备（客户端）建立连接并尝试读取这 2 个寄存器时，我收到错误消息：

...
    File "/home/workstation/devel/modbus_example/env_modbus/local/lib/python2.7/site-packages/pymodbus/server/async.py", line 83, in _send
        pdu = self.framer.buildPacket(message)
      File "/home/workstation/devel/modbus_example/env_modbus/local/lib/python2.7/site-packages/pymodbus/transaction.py", line 354, in buildPacket
        data = message.encode()
      File "/home/workstation/devel/modbus_example/env_modbus/local/lib/python2.7/site-packages/pymodbus/register_read_message.py", line 71, in encode
        result += struct.pack('>H', register)
    struct.error: cannot convert argument to integer

我应该如何将浮点值写入某个上下文？我找不到任何例子。

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