• Modbus 应用示例

    Modbus 应用示例

    • 此应用使用了一个Lua实现的modbus模块(modbus_lua)
    • 此应用使用SocketChannel和SerialChannel作为链路层
    • 更为详细的modbus数据采集可以参考: modbus_example

    代码:

    1. local class = require 'middleclass'
    2. --- 导入需要的模块
    3. local modbus = require 'modbus.init'
    4. local sm_client = require 'modbus.skynet_client'
    5. local socketchannel = require 'socketchannel'
    6. local serialchannel = require 'serialchannel'
    8. --- 注册对象(请尽量使用唯一的标识字符串)
    9. local app = class("XXXX_App")
    10. --- 设定应用最小运行接口版本(目前版本为1,为了以后的接口兼容性)
    11. app.API_VER = 1
    13. ---
    14. -- 应用对象初始化函数
    15. -- @param name: 应用本地安装名称。 如modbus_com_1
    16. -- @param sys: 系统sys接口对象。参考API文档中的sys接口说明
    17. -- @param conf: 应用配置参数。由安装配置中的json数据转换出来的数据对象
    18. function app:initialize(name, sys, conf)
    19.     self._name = name
    20.     self._sys = sys
    21.     self._conf = conf
    22.     --- 获取数据接口
    23.     self._api = sys:data_api()
    24.     --- 获取日志接口
    25.     self._log = sys:logger()
    26.     self._log:debug(name.." Application initlized")
    27. end
    29. --- 应用启动函数
    30. function app:start()
    31.     --- 设定回调处理函数(目前此应用只做数据采集)
    32.     self._api:set_handler({
    33.         on_ctrl = function(...)
    34.             print(...)
    35.         end,
    36.     })
    38.     ---获取设备序列号和应用配置
    39.     local sys_id = self._sys:id()
    40.     local config = self._conf or {
    41.         channel_type = 'socket'
    42.     }
    44.     --- 添加10个采集项
    45.     local inputs = {}
    46.     for i = 1, 10 do
    47.         inputs[#inputs + 1] = { 
    48.             name='tag'..i,
    49.             desc='tag'..i..' description',
    50.         }
    51.     end
    53.     --- 生成设备的序列号
    54.     local dev_sn = sys_id..".modbus_"..self._name
    55.     local meta = self._api:default_meta()
    56.     meta.name = "Modbus"
    57.     meta.description = "Modbus Device"
    58.     meta.series = "XXX"
    59.     --- 生成设备对象
    60.     local dev = self._api:add_device(dev_sn, meta, inputs)
    61.     --- 生成设备通讯口统计对象
    62.     local stat = dev:stat('port')
    63.     local client = nil
    65.     --- 获取配置
    66.     if config.channel_type == 'socket' then
    67.         opt = {
    68.             host = "127.0.0.1",
    69.             port = 1503,
    70.             nodelay = true,
    71.         }
    72.         print('socket')
    73.         client = sm_client(socketchannel, opt, modbus.apdu_tcp, 1)
    74.     else
    75.         opt = {
    76.             port = "/dev/ttymxc1",
    77.             baudrate = 115200
    78.         }
    79.         print('serial')
    80.         client = sm_client(serialchannel, opt, modbus.apdu_rtu, 1)
    81.     end
    82.     --- 设定通讯口数据回调
    83.     client:set_io_cb(function(io, msg)
    84.         --- 输出通讯报文
    85.         dev:dump_comm(io, msg)
    86.         --- 计算统计信息
    87.         if io == 'IN' then
    88.             stat:inc('bytes_in', string.len(msg))
    89.         else
    90.             stat:inc('bytes_out', string.len(msg))
    91.         end
    92.     end)
    93.     self._client1 = client
    94.     self._dev1 = dev
    95.     self._stat1 = stat
    97.     return true
    98. end
    100. --- 应用退出函数
    101. function app:close(reason)
    102.     print(self._name, reason)
    103. end
    105. --- modbus寄存器数据解析
    106. function decode_registers(raw, count)
    107.     local d = modbus.decode
    108.     local len = d.uint8(raw, 2)
    109.     assert(len >= count * 2)
    110.     local regs = {}
    111.     --- 按照无符号短整数进行解析
    112.     for i = 0, count - 1 do
    113.         regs[#regs + 1] = d.uint16(raw, i * 2 + 3)
    114.     end
    115.     return regs
    116. end
    118. --- 应用运行入口
    119. function app:run(tms)
    120.     local client = self._client1
    121.     if not client then
    122.         return
    123.     end
    125.     --- 设定读取的起始地址和读取的长度
    126.     local base_address = 0x00
    127.     local req = {
    128.         func = 0x03, -- 03指令
    129.         addr = base_address, -- 起始地址
    130.         len = 10, -- 长度
    131.     }
    132.     --- 读取数据
    133.     local r, pdu, err = pcall(function(req, timeout) 
    134.         --- 统计数据
    135.         self._stat1:inc('packets_out', 1)
    136.         --- 接口调用
    137.         return client:request(req, timeout)
    138.     end, req, 1000)
    140.     if not r then 
    141.         pdu = tostring(pdu)
    142.         if string.find(pdu, 'timeout') then
    143.             self._log:debug(pdu, err)
    144.         else
    145.             self._log:warning(pdu, err)
    146.         end
    147.         return
    148.     end
    150.     if not pdu then 
    151.         self._log:warning("read failed: " .. err) 
    152.         return
    153.     end
    155.     --- 统计数据
    156.     self._log:trace("read input registers done!")
    157.     self._stat1:inc('packets_in', 1)
    158.     --- 解析数据
    159.     local regs = decode_registers(pdu, 10)
    160.     local now = self._sys:time()
    162.     --- 将解析好的数据设定到输入项
    163.     for r,v in ipairs(regs) do
    164.         self._dev1:set_input_prop('tag'..r, "value", math.tointeger(v), now, 0)
    165.     end
    167.     --- 返回下一次调用run之前的时间间隔
    168.     return tms
    169. end
    171. --- 返回应用对象
    172. return app