Integrated Systems Programming

Embedded Systems

And

Systems Integration

What is System Integration

• Creating interconnection, control and communications between systems that would normally stand alone

• In other words “Interfacing”

• Computers or controllers at the heart of an integrated system may be deemed an “embedded system”

The Systems Integrator

As a systems integrator, your job is to:1. understand the interface requirements or

possibilities and determine best approach

2. plan the overall integration and the functionality of the system

3. Plan the user experience – “User Friendly”

4. Program the System

Interfaces

• Infra Red• Serial Communications• Relay contact closure• Switch contact closure• Ethernet• Wireless (R.F.)• Power Line Carrier• Proprietary interfaces

Infrared

• Used to control A.V. and some appliances(air conditioners, drape controls)

• Unidirectional

• Line of sight

• Proprietary issues

Characteristics of I.R.

• Infra Red is light that is invisible to the naked eye because it is outside the normal wavelength that we can see

• It is generated by an I.R. L.E.D.

• It is detected by I.R. receiver

• Serial digital signals are modulated onto the L.E.D. and demodulated after the detector

I.R. Signals

• The signal is serial data.

• I.R. works on line of sight.

• I.R. cannot go through objects

• I.R. can reflect as normal light

Distribution

• It is sometimes useful to have I.R. transferred between rooms

• It is sometimes useful to have I.R. generated in or behind a cabinet and control a device not in “line of sight”

• It is sometimes useful to have I.R. control equipment in a cabinet or wiring closet not visible to the handheld remote control or other I.R. emitter

Wireless I.R. distribution

Wireless I.R. distribution

In Cabinet Solution

Wired I.R. Distribution

Wired I.R. Distribution

Wired I.R. Distribution

Wired I.R. Distribution

Control System I.R.

• Crestron and other control systems can use I.R. for control.

• They typically use the same type of wired I.R. emitters seen above.

Control Processor

rs232

• Classic serial interface

• Positive control

• Hard wired

• Provides for 2 way (feedback)

• Not plug-and-play due to protocol choices

• DTE vs DCE issues

Relay Contact Closure

• Simple on/off• X-10 through universal module• Crestron Digital Outputs• PLC (Programmable Logic Controllers) systems

handle this well – commercial applications• Unidirectional • Positive control• Good for high current applications

• You must consider current/voltage limits!

Switch Closure

• Simple on/off for sensing status

• Proximity sensing, door open/close, trigger of events

• Crestron Digital Inputs

• Could be used for Power Probes

Ethernet• Becoming the standard

• Good for high speed communications between devices (100MBPS and rising)

• Good for networks of all kinds

• Internet/Intranet

• Telecommunications

• Some appliances are beginning to incorporate

• Some A.V. equipment

Wireless• Based on Radio Frequency

• Digital signals modulated onto R.F.

• Wireless Ethernet

• Easy to install

• Slower than wired systems

• Prone to interference and blocking

• Security issues

Power Line Carrier

• X-10 is most obvious example

• Other PLC communications is possible including TCPIP.

• Typically slow

• Prone to interference and signal loss

Proprietary Interfaces

• Examples:– Cresnet– Lutron MUX– A.V. device interconnect specific to 1

company. Typically a company may have a receiver that can control the DVD or CD player but only of their own brand.