By Andrew Gliga Cs 147What are Embedded Systems?Slide 3Slide 4What uses Embedded Systems?History of Embedded MachinesMore HistoryEven More HistoryCharacteristicsMicrocontrollersSlide 11Microcontrollers are SmallAspects of MicrocontrollersSystems on a Chip (SOC)Slide 15Embedded SoftwareEmbedded Systems MemoryThe EndBy Andrew GligaCs 147What are Embedded Systems?Similar to real computersThey have CPU, memory, I/OThough they have limited tasksCan only do specific things that they are designed forNo specific definition for Embedded Systems, some systems have one task, others have hundreds. Some have GUI, some do not even have a mode of interactionWhat uses Embedded Systems?Cars, Airplanes, Coffee Machines, MP3 players, cellphonesBasically any machine that needs to perform certain tasksThe Embedded Systems in these machines controls certain aspects, such as fuel injection, pilot controls, speedometers, and dispensing CoffeeHistory of Embedded MachinesComputers in the 1940's were too large and expensive to be used in portable tasks, even though they could perform simple tasks.Over time though, with smaller and smaller computers, they could be created for specific tasksMore HistoryCharles Stark Draper developed the first modern Embedded Machine for the Apollo Spacecraft, called the Apollo Guadance computer that helped make the Moon landing possible.Even More HistoryWith the introduction of the Microprocessor, Embedded Machines were able to take smaller and smaller forms.This allows smaller and lighter machines that control many of our devices today, such as our Cell phones, or MP3 playersCharacteristicsThey can only be used for specific tasks, not general tasksThey run with limited resourcesThey can also be a part of a larger system and used as a subsystemFor example: a car is the larger system, while the Embedded System is a subsystem of the carMicrocontrollersMicrocontrollers is what controls the embedded systemUnlike Microprocessors, they include memory and I/O. In a sense, they are like a mini computerThey implement AND, OR, XOR, NOT gatesExtremely compact and cheapMicrocontrollers are SmallAspects of MicrocontrollersWatchdog timersThey generally keep an eye on the system.When an error occurs in the system they enable a failsafe mechanism. Similar as a human resets a non-responsive machine, the Watchdog timer automatically 'resets' the Microcontroller to a normal state when it doesn't respond normally for a specified timeSystems on a Chip (SOC)Microcontrollers, while they are mini computers still require supporting circuits.Examples: Decoders, signal converts, or signal processorsSOC incorporates all these suporting circuits and a Microcontroller in one easy and compact chip. They are fast, small, and compact. They even consume less memory than having all the other chips that they replaceEmbedded SoftwareSoftware written for an embedded machine needs to have the specs of the machine in mind.The software is built in the Embedded System itselfSoftware also can not be fine tuned after the program is embedded onto the circuitNeed to get it right the first time!Embedded Systems MemoryThe Embedded System does not use virtual memory, since it relies on being quick.Embedded programmers have to be aware of the size of memory, since it is limited based on the machineThe
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