python modbus_tk模块学习笔记（rtu slaver例程）

GIT地址：https://github.com/ljean/modbus-tk
找到modbus rtu slaver 例程
用宝塔将例程复制到centos目录

#!/usr/bin/env python
# -*- coding: utf_8 -*-
"""
 Modbus TestKit: Implementation of Modbus protocol in python
 (C)2009 - Luc Jean - [email protected]
 (C)2009 - Apidev - http://www.apidev.fr
 This is distributed under GNU LGPL license, see license.txt
"""

import sys

import modbus_tk
import modbus_tk.defines as cst
from modbus_tk import modbus_rtu
import serial


PORT = 0
#PORT = '/dev/ptyp5'

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))

    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:
            cmd = sys.stdin.readline()
            args = cmd.split(' ')

            if cmd.find('quit') == 0:
                sys.stdout.write('bye-bye\r\n')
                break

            elif args[0] == 'add_slave':
                slave_id = int(args[1])
                server.add_slave(slave_id)
                sys.stdout.write('done: slave %d added\r\n' % (slave_id))

            elif args[0] == 'add_block':
                slave_id = int(args[1])
                name = args[2]
                block_type = int(args[3])
                starting_address = int(args[4])
                length = int(args[5])
                slave = server.get_slave(slave_id)
                slave.add_block(name, block_type, starting_address, length)
                sys.stdout.write('done: block %s added\r\n' % (name))

            elif args[0] == 'set_values':
                slave_id = int(args[1])
                name = args[2]
                address = int(args[3])
                values = []
                for val in args[4:]:
                    values.append(int(val))
                slave = server.get_slave(slave_id)
                slave.set_values(name, address, values)
                values = slave.get_values(name, address, len(values))
                sys.stdout.write('done: values written: %s\r\n' % (str(values)))

            elif args[0] == 'get_values':
                slave_id = int(args[1])
                name = args[2]
                address = int(args[3])
                length = int(args[4])
                slave = server.get_slave(slave_id)
                values = slave.get_values(name, address, length)
                sys.stdout.write('done: values read: %s\r\n' % (str(values)))

            else:
                sys.stdout.write("unknown command %s\r\n" % (args[0]))
    finally:
        server.stop()

if __name__ == "__main__":
    main()

查看centos串口号

[root@bogon /]# cat /proc/tty/driver/serial
serinfo:1.0 driver revision:
0: uart:16550A port:000003F8 irq:4 tx:0 rx:0 CTS|DSR|CD
1: uart:16550A port:000002F8 irq:3 tx:40867 rx:13240 DSR|CD
2: uart:unknown port:000003E8 irq:4
3: uart:unknown port:000002E8 irq:3
[root@bogon /]# ls -l /dev/ttyS*
crw-rw---- 1 root dialout 4, 64 12月 18 11:29 /dev/ttyS0
crw-rw---- 1 root dialout 4, 65 12月 18 12:39 /dev/ttyS1
crw-rw---- 1 root dialout 4, 66 12月 18 11:29 /dev/ttyS2
crw-rw---- 1 root dialout 4, 67 12月 18 11:29 /dev/ttyS3
[root@bogon /]# 

这里我用的
/dev/ttyS1
刚才复制的例程
修改

PORT = 0
#PORT = '/dev/ptyp5'

为

#PORT = 0
PORT = '/dev/ttyS1'

centos下运行例程

python licheng.py

输出

RtuServer /dev/ttyS1 is opened
running...
enter 'quit' for closing the server

输入

set_values 1 0 0 1 2 3 4 5 6 7 8 9 10

返回

done: values written: (1, 2, 3, 4, 5, 6, 7, 8, 9, 10)

modbus poll