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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”
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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: • understand the interface requirements or possibilities and determine best approach • plan the overall integration and the functionality of the system • Plan the user experience – “User Friendly” • 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
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.
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.