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Introduction to Embedded Systems. What is an Embedded System?. Electronic devices that incorporate a microprocessor or microcontroller within their implementation. Microprocessor of embedded system is hidden from user. No Mouse, Kbd, monitor, etc. Embedded Systems Applications.
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What is an Embedded System? • Electronic devices that incorporate a microprocessor or microcontroller within their implementation. • Microprocessor of embedded system is hidden from user. • No Mouse, Kbd, monitor, etc.
Embedded Market • Embedded:desktop = 100:1 • Average #embedded processors in the resident home estimated about 50
Embedded System • CPU and Software • Memory Storage: ROM, RAM, PROM, EPROM • Input: knobs, buttons, probes, sensors, A/D communications signals, panels • Output: LCD display, microwave radiation, A/D communication signals • Outputs = functions (inputs, elapsed time, …)
Common Design Criterion • Production cost constraints • Processing power(limited) • Memory constraints(limited) • Development cost(low) • Number of units • Expected life time( may not be long) • Reliability
C for embedded software • The most popular language for embedded systems ( over 80%) • A high level language • Compact, efficient code for almost all processors • Both high-level and low-level features • Direct hardware control, without losing the benefits of a high-level language • Appropriate for 8-bit to 64-bit processors • For systems with bytes, KB, MB of memory
Typical Hardware • Microprocessor: execute code • Memory: ROM, RAM, PROM, EPROM, Flash • Embedded systems do not have the following - a keyboard - a screen - a disk drive - CD, speakers, microphones, diskettes, modems • Embedded systems have: serial port, network interface, sensors, AD/DA
Design Goal of Embedded System • Mission critical and life-threatening • 24/7/365 and can’t reboot at all • No human intervention • Multitasking and scheduling • Optimized I/O by Assembly Language • Limits, Inaccuracies of Fixed Precision • Consumer market: Minimize Manufacturing Cost • Fast time to market required • No chance for future modification
Design Goal of Embedded System • Handle a lot of volume of data in a short period of time • React to external events quickly • Setting up equipment to test embedded software • Without a screen or keyboard, finding out what the software is doing wrong • Must be able to handle any situation without human intervention • Memory is limited on embedded systems, and you must make the software and the data fit into whatever memory allows
Design Goal of Embedded System • You will need special tools to get your software into embedded systems (burner) • Portable systems must run on battery power, and the software in these systems must conserve power • Embedded systems have a microprocessor and a memory. Some have a serial port or a network connection. They usually do not have keyboards, screens, or disk drives.