dasgib / ruby_s7plc

Ruby library for Simatic S7-300 PLC data exchange

ruby_s7plc

Ruby library for Siemens Simatic S7-300 PLC data exchange.

Quick start

  require 'simatic'
  Simatic::Plc.exchange('192.168.0.1') do |plc|
    plc.write('db1.dbw2'=> 0xffff)
    res = plc.read('db1.dbw2')
    puts "#{res.verbal} = #{Simatic::Types::Word.parse(res.value)}"
  end

Reference

Install

  # in Gemfile
  gem 'simatic'

or

  gem install simatic

Requires

  require 'simatic'

Client creation

  plc = Simatic::Plc.new('192.168.0.1')
  plc.connect
  # Add you code here
  plc.disconnect

Or with block:

  Simatic::Plc.exchange('192.168.0.1') do |plc|
    # Add you code here
  end

You can specify rack and slot parametrs by adding a hash args to functions or , defaults rack: 0, slot: 2

Simatic::Plc.new('192.168.0.1', rack: 0, slot: 2) ...
Simatic::Plc.exchange('192.168.0.1', rack: 0, slot: 2) do |plc| ...

Exchange functions

plc.read('db1.dbx0.0')

This function can understand verbal adressing in Simatic Step 7 notation, like M0.0, DB1.DBB23, C0, T1 and so on. Result of this funtion is a MemoryMapper object that can give you raw_data and value of plc response. After this function you should use SymaticTypes module to convert data into ruby undestandable types.

plc.write('db1.dbw2' => 0xffff)

This function take a hash with verbal addresses and values to write pairs. Values can be simple types like Integer, Float, one char String, Date, Time or it can be special types of SimaticTypes Module.

plc.write('db1.dbb18[2]'  => Simatic::Types::S5time.new(711.3))

Convertation functions

Simatic::Types::Bool   # use TrueClass, FalseClass
Simatic::Types::Byte   # use Numeric
Simatic::Types::Word   # use Numeric
Simatic::Types::Dword  # use Numeric
Simatic::Types::Int    # use Numeric
Simatic::Types::Dint   # use Numeric
Simatic::Types::Real   # use Numeric
Simatic::Types::S5time # use Numeric as a time in seconds
Simatic::Types::IECTime     # use Numeric as a time in seconds
Simatic::Types::IECDate     # use Numeric as a days
Simatic::Types::TimeOfDay   # use Numeric as a seconds from start of day 0:00 a.m.
Simatic::Types::DateAndTime # use Time
Simatic::Types::S7String    # use String with length of buffer param

Each of this objects take Ruby types with new method and gives you with parse method:

Simatic::Types::S5time.new(10.2)
Simatic::Types::S5time.parse(res.raw_data)
Simatic::Types::S7String.new("hello world", 15) # 15 is a length of buffer (address for this string to read or write must be [17])

For special types like S5time, IECTime, IECDate, TimeOfDay, DateAndTime, S7String you should use raw_data method instead of value, because if you write an adress with [] notation of bytes value will return a array of chars.

Waring

This is beta code! Do not use it in danger manufactory!

See also

Father and oldest of all open Simatic communication libraries is Libnodave project:

• http://libnodave.sourceforge.net/

Another interesting projects:

• https://github.com/kprovost/libs7comm
• https://github.com/kirilk/simatic
• https://github.com/killnine/s7netplus
• https://github.com/plcpeople/nodeS7