Last Modified: 29 March 2001

Most of the available I/O systems respond within 10...150 milliseconds, fine for process control systems where response is not critical, but far too slow for production machines where every millisecond counts.

Cdios Modular I/O System from CD Systems (www.cd-systems.com) has been developed for the machine and instrument designers who need I/O modules that can respond in only a few milliseconds.

Features are the tricks that make a system smart. With CAN Devices, event-driven communication can be implemented - an input node will generate an I/O message only when its signal changes or a value has reached a limit.

The event-driven Cdios Modular I/O System means that requests for an input status are not repeated over and over again - the input node will send message only when it changes. The advantage of this is less communication on the bus, lower bus speed, lower EMC disturbance.

An example of one of the many CD Systems Features is the One-shot-timer on each digital output: after the one-shot delay time the output will switch-off automatically, exactly on the millisecond, so the application program does not have to run a delay loop and send a switch-off message. 

Communication during demanding applications can be heavy. The use of the event feature and other time and software saving features can improve the application software efficiency. But it would be even more efficient if repeating tasks could be performed locally ...

Another advantage! Cdios Module I/O System controllers can be programmed to perform local tasks. The main application can send a Start of Task command, and the Cdios controller can respond with just a status or an error message. 

One of the advantages of a bus system with smart devices is the ability to build-in diagnostic functions. Diagnostic data can save a lot of time and money when running systems. 

Cdios Modules are supplied with all kinds of diagnostic functionality: not only can the status of inputs, outputs and positions be read, but temperature sensors can have open loop detection, even the digital outputs can have open loop and short circuit detection. 

With a modular I/O system the user can select a combination of I/O devices he prefers, but some available systems differ in the way they are mounted, or connect to each other, etc. 

The design of the Cdios Modular I/O System is based on many years of experience: each module is a DIN rail unit with a flexible interconnection and its own power connection, the I/O connections are electrically isolated and have detachable connectors. 

A Cdios Modular I/O System can be used in machine building applications but also in Process Control Systems. 

Cdios Systems are often used in scientific applications in combination with labVIEW(tm) and with industrial companies that need the unique Cdios features and performance.

There are several available communication protocols for CAN: 
CANopen is a high-level CAN protocol supported by the industry CANbus organization CiA, mostly used in Europe but becoming increasingly popular in USA; 
DeviceNet was developed by Allen Bradley, and is supported by ODVA, used widely in the USA. 

CD Systems implement both CANopen and DeviceNet from the ground up (that's our performance secret). We know how both work in detail - a full description of the protocols is available on our Internet site in a protected section (please request a password by e-mail). 

Buying a device or system is one thing, getting support from someone who knows how it really works is quite another! After-sales support is a top priority for CD Systems.

At CD Systems, we support our Cdios System in every way we can: all data, descriptions, connections, specification, configuration software and firmware up-dates are available constantly on our website. 
We usually answer e-mails and other questions within 24 hours.

Prices of many I/O systems are hard to find either on printed lists or on the Internet.

The prices of Cdios Modules are not secret. Feel free to compare the price of Cdios with the price of competitors, but don't forget to accurately compare specifications! 
The prices of our digital modules, for instance, may be equal to competitors, but other Cdios Modules have far better specifications and a far lower price.