Embedded Systems

2 A “short list” of embedded systems And the list goes on and on Anti-lock brakes Auto-focus cameras Automatic teller machines Automatic toll systems Automatic transmission Avionic systems Battery chargers Camcorders Cell phones Cell-phone base stations Cordless phones Cruise control Curbside check-in systems Digital cameras Disk drives Electronic card readers Electronic instruments Electronic toys/games Factory control Fax machines Fingerprint identifiers Home security systems Life-support systems Medical testing systems Modems MPEG decoders Network cards Network switches/routers On-board navigation Pagers Photocopiers Point-of-sale systems Portable video games Printers Satellite phones Scanners Smart ovens/dishwashers Speech recognizers Stereo systems Teleconferencing systems Televisions Temperature controllers Theft tracking systems TV set-top boxes VCR’s, DVD players Video game consoles Video phones Washers and dryers

Characteristics of Embedded Systems single functioned tightly constrained design matrix reactive & real time

Hardware Architecture of Embedded System

Development Flow

Design Matrix Nonrecurring Engineering Cost (NEC) Unit cost see later Size ( physical, memory, #gates #transistors) Will be addressed in a separate presentation called “What is ASIC” Performance (execution time, latency, throughput) Power Time to Prototype see later Time to Market see later Maintainability

7 NRE and unit cost metrics Compare technologies by costs -- best depends on quantity – Technology A: NRE=$2,000, unit=$100 – Technology B: NRE=$30,000, unit=$30 – Technology C: NRE=$100,000, unit=$2 But, must also consider time-to-market

8 Time-to-market Time required to develop a product to the point it can be sold to customers Market window – Period during which the product would have highest sales Average time-to-market constraint is about 8 months Delays can be costly Revenues ($) Time (months)

9 Losses due to delayed market entry Simplified revenue model – Product life = 2W, peak at W – Time of market entry defines a triangle, representing market penetration – Triangle area equals revenue Loss – The difference between the on-time and delayed triangle areas On-time Delayed entry Peak revenue Peak revenue from delayed entry Market rise Market fall W2W Time D On-time Delayed Revenues ($)

Processor Technology General Processor ( e.g. Microprocessor) Single Purpose Processor (e.g. Digital Signal Processor or Digital Controller) Application Specific Processor (ASIP)

Processor Technology General Processor (GP) -concentrate on software development - favourable NEC, time to prototype & maintainability Single Purpose Processor (SPP) -concentrate on hardware -favourable performance, power, size & unit cost Application Specific Processor (ASIP) – optimised for a particular class of applications (e.g. microcontroller, DSP) a compromise between GP and SPP.

IC Technology Full Custom : VLSI (Very Large Scale Integration), full mask needed, high NEC, long turn-round time. Semi-Custom (Gate Arrays and Standard Cell) also called ASIC (Application Specific IC) Mask needed for interconnections. FPGA: Connections configured programmatically

FPGA Smallest “Brick” =Logic Cell

FPGA = matrix of many THOUSANDS Logic Cells Interconnections are configured by the User

Example:Interconnect of Carry Signals

IO Cells Connect Logic Cells to the Pins

FPGAs have also On Chip RAM

Dual Port RAM

Last Slide: Implementation Discrete Design on PCB System On Chip (SOC) will be done in Workshops !!!