Python modbus rtu slave+mysql+随机数生产模拟数据

目的：
通过读取mysq’l rtu数据表地址数值，用python在原值得基础上加上随机数（0-9）
mysql数据
数据结构

数据列表（部分）

Python代码

#!/usr/bin/env python
# -*- coding: utf_8 -*-
import sys
import time
import pymysql
import json
import random
import modbus_tk
import modbus_tk.defines as cst
from modbus_tk import modbus_rtu
import serial 
#PORT = 0
PORT = '/dev/ttyS1'
mysqlhost="localhost"
mysqluser="python"
mysqlpassword="python" 
mysqlport=3306
mysqldatabase="python"
mysqlcharset='utf8'
#读取数据库触发条件规则
def mysql_rule(myserver,slaveid):
    db = pymysql.connect(mysqlhost, 
                     mysqluser, 
                     mysqlpassword, 
                     port=mysqlport,
                     database=mysqldatabase, 
                     charset=mysqlcharset)
    cursor = db.cursor(cursor =pymysql.cursors.DictCursor) #设置游标类型为DictCursor以后，生成的就是字段名和值组成的键值对字典了
    sql = "SELECT * FROM rtu where slave_id='"+str(slaveid)+"'"
    print(sql)
    try:
        cursor.execute(sql) 
        results = cursor.fetchall()
        value=[] 
        for row in results:
          value=[]  
          slave_id = row['slave_id']
          name = row['name']
          addr = int(row['addr'])
          myvalue =int(row['value'])+random.randint(0,9)
          value.append(myvalue)
          print(str(slave_id)+" "+name+" "+str(addr)+" "+str(myvalue))
          myslave = myserver.get_slave(slaveid)
          myslave.set_values(name,addr,myvalue)
          value = myslave.get_values(name,addr, 1)
          sys.stdout.write('done: values written: %s\r\n' % (str(value)+' id'+str(row['id']))) 
        # 打印结果
          
    except:
        print("Error: unable to fecth data")
    cursor.close()
    db.close()
def main():
    """main"""
    logger = modbus_tk.utils.create_logger(name="console", record_format="%(message)s") 
    #Create the server
    server = modbus_rtu.RtuServer(serial.Serial(PORT,baudrate=9600)) 
    try:
        logger.info("running...")
        logger.info("enter 'quit' for closing the server") 
        server.start() 
        slave_1 = server.add_slave(1)
        slave_1.add_block('0', cst.HOLDING_REGISTERS, 0, 100)
        while True:
                slave_id = 1
                name = '0'
                address = int('0')
                mysql_rule(server,slave_id)
                time.sleep(1) # 休眠1秒
    finally:
        server.stop()

if __name__ == "__main__":
    main()

测试结果

在这里插入代码片

[root@bogon lqj]# python rtu.py
RtuServer /dev/ttyS1 is opened
running...
enter 'quit' for closing the server
SELECT * FROM rtu where slave_id='1'
1 0 0 66
done: values written: (66,) id1
1 0 1 68
done: values written: (68,) id2
1 0 2 63
done: values written: (63,) id3
1 0 3 64
done: values written: (64,) id4
1 0 4 60
done: values written: (60,) id5
1 0 5 68
done: values written: (68,) id6
1 0 7 69
done: values written: (69,) id7
1 0 8 66