Polygon

Purpose

The central place in the control systems take the controlling algorithms, which are realized by the controller"s software. The development and debugging may take a long time, besides, during the exploitation it is necessary to adapt it to the changing conditions.

At present time the progress reached such a level that the controllers" technical means have, in general, the common elements base, equal ideas in development and the production conditions. . This made the majority of controllers similar in possibilities and exploitation characteristics.

The standards are also worked out for the controllers software. These standards help to unify the approaches to development of such systems. But behind the similar form there hides the different contents, which gives a possibility to create a flexible control system or not.

It is very important for "Promautomation" to have the powerful software development system, which can allows to create regulators with small response time, distributed systems with different equipment enabled, integrate the own developed boards with controllers. At the same time each system should be supplied with full documentation set so that the staff could search the system"s work, make necessary corrections. The necessity in corrections arises when changing equipment, for example sensors or changing the modes of a technological set. POLYGON allows deciding high complexity tasks since it is aimed on creating efficient executive code with small response time. It includes:

• graphic development environment for creating and debugging the software;
  
• functional blocks library;
  
• realtime dispatcher;
  
• interruption processing dispatcher.
  

Functional features

The POLYGON system consist of:

• configurator;
  
• graphic editor;
  
• project manager.
  

The components of POLYGON are built so that they allow automation of many tasks of development and documentation of the software.

Configurator

Functions:

• creating object"s description as the structure:
  OBJECT -> AGGREGATE -> MEASUREMENT AND CONTROL CHANNELS;
  
• creating the controller description structure
  CRATE -> I/O BOARD -> REGISTER -> CHANNEL
  or
  CRATE INTERFACE BOARD-> INTERFACE -> REMOTE DEVICE;
  
• linking the object"s channel with controller channels;
  
• creating i/o software and graphic editor interface program.
  

Configurator implements an important function of program"s external connections maintenance. The latter delivers the developer from the necessity to trace the routing process, setting the controlling sequences etc. The developer creates a basic software configuration of the controller module, containing the interference with external objects via the interface boards. This program can be subsequently edited and adjusted.

Graphic editor

The basic work on realization of controlling algorithms of a plant is implemented in the graphical editor.

Graphical editor functions:

• creating controller software;
  
• software compilation;
  
• transmitting the software into the controller;
  
• software launch, real time debugging;
  
• service functions;
  
• help file;
  
• developing user"s functional blocks.
  

The controller software consist of interrelated subprograms, with the set "workstation". The workstation determines the mode of program"s work: real time or background mode functioning. Each program is assigned an execution order.

The editor has a set of functional menus, help file. The editor screen is the two worksheets containing user defined subprograms. Each subprogram consists of two interrelated functional blocks. Functional block is a complete algorithm. It receives an input signals, processes it accordingly and forms the output signals. The structure of each block is stored in the database. The user chooses appropriate blocks, grounding his choice on their description and establishes connections between the inputs of one group of blocks with the outputs of the others. The connections are freely established as within one worksheet, so within one program, also between different programs and workstations. The worksheets fields contain information of the presented blocks connections.

Functional blocks library

The functional blocks library at present time includes 360 blocks and its quantity increases as the new ones are developed and the old ones are debugged. The block are united into following groups:

• regulators: PD, PID-regulators, linear regulator, aperiodic filters, Butterworth filters, gradient filter, limiters etc.
  
• generators and timers: impulse generator, start with delay, stop with delay, signals generator, logical timer with a notch, half, impulse generator with the set off-duty factor.
  
• triggers: S-dominant trigger, R-dominant trigger, D-trigger, DV-trigger etc.
  
• Arithmetic: addition, subtraction, multiplication, division, square root, inverse value, absolute value etc.
  
• Logical: AND, OR, negation, AND with negation, OR with negation etc.
  
• Messages and archives: message archives, parameters archives, massif, text message.
  
• Interfaces: output bumper, input bumper, controller connection interface, NetBIOS, interface with ADAM modules, interface with Proface, ComDDE-interface, Com-interface with an Omron controller, interface by Fieldbus (slave-module), UDP-protocol, TCP/IP Server, interface with Hitache drive, interface for Modbus connection.
  
• "black box"
  
• control panels: blocks for working with alpha-numeric displays for organizing "menu", data i/o.
  
• system (get time and date, set time and date, program shutdown.
  
• i/o modules (blocks for connecting forty types of modules).
  
• integer arithmetic.
  
• type converters and constants (service functions for data type converting).
  
• operations with registers: blocks for uniting signals into registers, operations on registers, blocks for extracting signals from registers
  
• trigonometric functions (trigonometric blocks).
  
• jumpers, relays and multiplexers.
  
• work with the lines.
  

It is essential that the blocks are debugged and checked in numerous projects. Applying other approaches makes the process of revealing all evident and latent errors more long.

Many blocks have a dinamically adjusted quantity of inputs/outputs. This substantially alleviates the modification of the software

Realization features

The POLYGON system library is an open one, i.e. it allows adding the new functional blocks, which maintain execution of user"s specific tasks. POLYGON contains the wizard that helps a user to add a new functional block to the library. Besides, a user may add a help part for every new block. Function blocks are placed in pages and connect each other by links.

For documentation of the created project the graphic editor contains the printing function. On the print out the project is displayed in the same form as on the screen: each paper sheet corresponds to a project page. Besides, each page is completed by a frame and ESCD stamp.

After program"s compilation the executable file is copied into the controller and there it is compiled and debugged. In the debugging mode every current value of the blocks is displayed on the editor"s screen. Creating the necessary signals on the boards interfaces we can check the work of algorithms in different situations. For debugging complex systems we use the objects models, which allows the most complete test of the whole system.

A necessary peculiarity of POLYGON is that the principles it contain allow its usage as a shell which can be filled with whatever contents. This gives an opportunity to use POLYGON for creating software for other hardware and different operational systems. POLYGON is the system, which helps to speed up the process of software development, make it clear, unify the approaches to task management. Finally this ensures the high quality of the customer"s system work .