Comparing Features

The table below compares and contrasts the similarities and differences between UCOS and traditional systems.

UCOS	Traditional Control Systems
Allows regulatory, discrete, and sequential control to be created with a single tool through graphical and object-oriented software techniques. It produces the functional equivalent of function block and rung ladder logic programming.	Regulatory, discrete, and sequential control are configured using multiple, separate tools.
Includes standard device objects and the ability to create user-definable device objects, all of which are reusable, yet unique.	Most systems do not have inherent support for templating or starter libraries of control logic. Any reuse of logic typically requires significant manual customization.
Encompasses all project components – from control logic to graphical symbols – in a single database.	Multiple development tools require multiple files to store various types of configuration information, such as tags, graphics, and logic.
Performs all addressing via structured tag names – no direct memory addresses are used.	PLC-based systems require direct memory addresses and complicated mnemonic naming conventions to maintain connections among rung ladder logic programs and the HMI software. Effectively, you must manage and coordinate two databases of configuration information.
UCOS	Traditional Control Systems
Non-proprietary, off-the-shelf components at all levels – from workstations, to controllers, to I/O – are available from multiple vendors. Simultaneous support for multi-vendor I/O and competitive sourcing make for cost-effective implementation and expansion.	Proprietary and/or single-source components are often required. Non-competitive sourcing makes for higher costs at all levels.
HMI nodes, controllers, I/O, devices, data servers, and instrumentation can be added or deleted to meet changing control system and business requirements. Multiple facilities can be connected to provide area-wide control.	Typically, the controller is a closed unit with no place to add cards. Sometimes minimal expansion is possible by adding other cards in the rack holding the controller.
Standard memory chips in the development, HMI, and controller units provide low-cost expandability.	A new controller may need to be purchased to gain additional memory to hold new control programs or functionality.
The development and HMI nodes run industry-standard Windows 2000/XP, which offers security along with connectivity to thousands of other software applications.	Engineering and operator workstations in DCS systems often run some form of UNIX.
UCOS	Traditional Control Systems
The controller runs QNX, an industry-standard, real-time operating system that includes full, open systems networking capability, the ability to run other software, and the ability to exchange data with other software using DDE, ODBC, and other data sharing protocols.	Controllers use some form of proprietary operating system (often no more than a low-level executive or task manager) that is typically embedded and not accessible. It has one purpose: to execute the proprietary control logic of that vendor's system. Connectivity to third-party or custom applications is limited or nonexistent.
Communications based on non-proprietary TCP/IP that can operate over affordable, off-the-shelf communications equipment.	Frequently based on proprietary protocols that require expensive proprietary hardware.
Automatically incorporates report-by-exception communications that maximize network throughput.	No pre-configured communications. Engineers must carefully program PLCs and the HMI to manage network traffic.