Embedded System

1. Embedded System

2. What is an Embedded System? • Computing systems embedded within electronic devices • Hard to define • Nearly any computing system other than a desktop computer • “A computer that is a component in a larger system, and is not visible as a computer to a user of that system.” • “A programmable component of subsystem providing some intelligence functions to the system of which it is a part.”

3. What is an Embedded System? • A microcontroller based system. • Built into a device to control a function or a range of functions. • Not designed to be programmed by the end-user (like a PC). • Executes an in-built single program repeatedly. • Tight coupling between hardware and software. • Designed to work in highly constrained environments. • Low cost, low power, small, fast, etc. • Reactive and real-time • Continually reacts to changes in the system’s environment • Must compute certain results in real-time without delay

5. Embedded Systems • Automotive systems • Airplanes • Toys • Medical Devices

6. Example Embedded Systems

7. Microcontroller Example

8. Microprocessor vs. Microcontroller

12. Pin Details of 8051

13. Microcontroller Market • Shipments- > 16 Billion in 2000, 8 bit > 1/2 market • Major Players: • Microchip 16Fxx • Intel 8051 • Motorola MC68HCxx • National COP800 • SGS/Thomson ST62 • Zilog Z86Cxx

14. Shipments

15. Programming Languages • ASM • Low level • Full Control • BASIC, Forth, LOGO • Interpreted • Easy to use • Slow • C • Most widely used • HiTech C • Microchip C • CCS PIC C

16. What is the Process ? • Write you program in MPLAB IDE • C or ASM • Compile your program • CCS C Compiler • Transfer your program • Puts HEX file into the PIC • Use PICSTART and MPLAB • “Burns your app into the PIC” • Insert your PIC • Power it Up

17. AVR Microcontroller

18. Introduction The AVR is a modified Harvard architecture8-bitRISC single chip microcontroller which was developed by Atmel in 1996. The AVR was one of the first microcontroller families to use on-chip flash memory for program storage, as opposed to one-time programmable ROM, EPROM, or EEPROM used by other microcontrollers at the time.

19. Device overview • The AVR is a modified Harvard architecture machine where program and data are stored in separate physical memory systems that appear in different address spaces, but having the ability to read data items from program memory using special instructions. • Basic families • AVRs are generally classified into six broad groups: • tinyAVR — the ATtiny series • 0.5–8 kB program memory • 6–32-pin package • Limited peripheral set • megaAVR — the ATmega series • 4–256 kB program memory • 28–100-pin package • Extended instruction set (Multiply instructions and instructions for handling larger program memories) • Extensive peripheral set • XMEGA — the ATxmega series • 16–384 kB program memory • 44–64–100-pin package (A4, A3, A1) • Extended performance features, such as DMA, "Event System", and cryptography support. • Extensive peripheral set with DACs

20. Application-specific AVR • megaAVRs with special features not found on the other members of the AVR family, such as LCD controller, USB controller, advanced PWM, CAN etc. • FPSLIC (AVR with FPGA) • FPGA 5K to 40K gates • SRAM for the AVR program code, unlike all other AVRs • AVR core can run at up to 50 MHz [5] • 32-bit AVRs • Main article: AVR32 • In 2006 Atmel released microcontrollers based on the new, 32-bit, AVR32 architecture. They include SIMD and DSP instructions, along with other audio and video processing features. This 32-bit family of devices is intended to compete with the ARM based processors. The instruction set is similar to other RISC cores, but is not compatible with the original AVR or any of the various ARM cores.

21. AVR Pin Details