modbus_tk模块

 1 # -*- coding: utf_8 -*-
 2 
 3  
 4 import serial
 5 import modbus_tk
 6 import modbus_tk.defines as cst
 7 from modbus_tk import modbus_rtu
 8 
 9 def mod(PORT="com10"):
10     #print("加载modbus_tk 完成")
11     red = []
12     alarm = ""
13     try:
14         #设定串口为从站
15         master = modbus_rtu.RtuMaster(serial.Serial(port=PORT,
16         baudrate=9600, bytesize=8, parity=‘N‘, stopbits=1, xonxoff=0))  
17         master.set_timeout(5.0)
18         master.set_verbose(True)
19             
20         #读保持寄存器 03H 1站号 地址2700 长度0-42 
21         red = master.execute(1, cst.READ_HOLDING_REGISTERS, 2700, 43) #这里可以修改需要读取的功能码
22         #print(red)
23         alarm="正常"
24         return list(red),alarm 
25     
26     except Exception as exc:
27         #print(str(exc))
28         alarm = (str(exc))
29         
30     return red, alarm      ##如果异常就返回[],故障信息
31     
32 if __name__ == "__main__":  
33     mod()

        #读保持寄存器 03H 1站号 0地址 长度2 
        logger.info(master.execute(1, cst.READ_HOLDING_REGISTERS, 0, 2))
        #01 03 00 00 00 02 C4 0B


        # 读输入寄存器 04H    
        logger.info(master.execute(1, cst.READ_INPUT_REGISTERS, 0, 8))
        #反馈：01 04 00 00 00 08 F1 CC

        
        # 读线圈寄存器 01H   
        logger.info(master.execute(1, cst.READ_COILS, 0, 6))
        #反馈：01 01 00 00 00 06 BC 08


        
        # 读离散输入寄存器 02H
        logger.info(master.execute(1, cst.READ_DISCRETE_INPUTS, 0, 16))
        #反馈：01 02 00 00 00 10 79 C6 



        # 单个读写寄存器操作 06H
        # 写寄存器地址为0的保持寄存器 06H  
        logger.info(master.execute(1, cst.WRITE_SINGLE_REGISTER, 0, output_value=6))
        #反馈：01 06 00 00 00 06 09 C8 
        logger.info(master.execute(1, cst.READ_HOLDING_REGISTERS, 0, 1))
        #反馈：01 03 00 00 00 01 84 0A


        
        # 写寄存器地址为0的线圈寄存器，写入内容为0（位操作） 05H
        logger.info(master.execute(1, cst.WRITE_SINGLE_COIL, 0, output_value=0))
        #反馈：01 05 00 00 00 00 CD CA 
        logger.info(master.execute(1, cst.READ_COILS, 0, 1))
        #反馈：01 01 00 00 00 01 FD CA


        
        # 多个寄存器读写操作 10H
        # 写寄存器起始地址为0的保持寄存器，操作寄存器个数为4
        logger.info(master.execute(1, cst.WRITE_MULTIPLE_REGISTERS, 11, output_value=[20,21,22,23]))
        #反馈：01 10 00 0B 00 04 08 00 14 00 15 00 16 00 17 AB A9
        logger.info(master.execute(1, cst.READ_HOLDING_REGISTERS, 0, 4))
        #反馈：01 03 00 00 00 04 44 09