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Introduction to Embedded Systems. Read Chapter 1 ( David E. Simon, An Embedded Software Primer ). What is an Embedded System (E.S.)?. Embed : Definition 1: to fix (something) firmly and deeply (Longman Dictionary)
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Introduction to Embedded Systems Read Chapter 1 (David E. Simon, An Embedded Software Primer)
What is an Embedded System (E.S.)? • Embed: • Definition 1: to fix (something) firmly and deeply (Longman Dictionary) • Definition 2: to enclose closely in a surrounding mass (Webser Dictionary) • System: implicitlya controlling system. Embedded Systems Development Introduction Saâd Biaz
Logical View of an Embedded System Control System Some Function Embedded Systems Development Introduction Saâd Biaz
Key Differences with PCs • React to external events that may be particularly rapid • Elevator on a sky-scrapper at 7:45am or 4:55pm • Missile flying at low altitude over a mountainous area • Must handle unusual events • A user blocking an elevator door, power blackout, memory failure • Task request with deadlines Embedded Systems Development Introduction Saâd Biaz
Required Features for E.S. • Throughput • Response • Testability • Low power • Reliability • Safety • Maintainability • Security • Availability • Cost • Size/Weight • Survivability Embedded Systems Development Introduction Saâd Biaz
Explosive Controlling system 170Kops 30 tons 200 KW ENIAC for Smart Bombs (1948) • Keeping the scale: the Atlas rocket would be needed to deliver a firecracker! • Up to the 70’s, embedded systems did not make sense for general public usage Embedded Systems Development Introduction Saâd Biaz
What Made E.S. Possible ?Small and Cheap • 1971: Intel 4004, first microprocessor (4bits), initially for a calculator. • 1981: IBM chooses Intel 8088 for the first PC. • Microprocessors get so cheap that microprocessor-based control systems become the rule. • Only limit: processing time. Embedded Systems Development Introduction Saâd Biaz
Products with Embedded Systems ? • Of 4 billions microprocessors/microcontrollers sold per year, 95% are for embedded products: • VCRs, DVD players • Cell phone • Microwave • Washer • Camera • Cars (antilock brake system, air-bag, gas injection, electricity distribution..) • Printers, copiers • ……….. Embedded Systems Development Introduction Saâd Biaz
Evolution of Embedded Systems • Hardwired systems initially • Microprocessor-based • Microcontroller-based • Specialized (application) processors Embedded Systems Development Introduction Saâd Biaz
Address Bus Digital outputs (parallel port) Digital inputs (parallel input) Serial port Data Bus Analog input/output Microcontroller Specialized Processors Evolution of Embedded Systems (2) mP LED Memory System I/O Switch Temperature Sensor USB 802.11 LCD Embedded Systems Development Introduction Saâd Biaz
Evolution of Embedded Systems (3) Popular microcontrollers • 8-bit : Intel 8051, Intel 80188, Motorola 6805, Motorola 68hc11, Zilog • 16-bit: Intel 80186, Motorola 683xx family • 32-bit: Intel 80386 EX, PowerPC family • More recent: • ATMEL line of products Embedded Systems Development Introduction Saâd Biaz
Evolution of Embedded Systems (4) Intel PXA250 Embedded Systems Development Introduction Saâd Biaz
Evolution of Embedded Systems (5) Intel PXA800F Cellular processor Embedded Systems Development Introduction Saâd Biaz
I/O of Embedded Systems • Application dependent: switches, sensors, hexadecimal keyboard, LCD, basic keypads, communication cards, LEDs • Rarely: • Monitor, hard-drive, secondary storage, mouse, keyboard, printer, … Embedded Systems Development Introduction Saâd Biaz