Systems Engineering Andrew Schaumberg SE411: 2005/Mar/10.

Systems Engineering

Andrew Schaumberg

SE411: 2005/Mar/10

SE411: 2005/Mar/10, Andrew Schaumberg

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What?The function of systems engineering is to guide theengineering of complexsystems.

Why?• Software is just one aspect of device implementation.• SE concepts applicable to physical implementation.• Holistic benefits. Coupling. Optimization.

-Kossiakoff and Sweet,Systems Engineering


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Case Study: Guitar

Why?• Familiar system.• Reengineered already.• Simple architecture.

Architecture revision history

Guitar


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Lute

Requirements:• Powerless• Easy to build• Durable• Pleasant• Easy to play

Cons:• Terrible to tune• Poor sustain


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Mandolin• Tuned better• High pitch, bad sustain

Acoustic guitar• Tunes like mandolin• Low pitch, sustain a bit better

Lute successors


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Problem: Tone control• Acoustic resonant cavities fixed

Solution: Transduce sound• Electric signal easy to shape

Options:• Microphone• Pickup


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Microphone

Pro: Cheap add-onCon: Generally poor frequency response

Pickup

Pro: Simplifies architectureCon: Requires architecture reengineering


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Consider Requirements

Need a quick fix for some old acoustics?• Get a mic

Need something new that is cheap and lasts?• Get an electric

Rough SE analogy:Functional vs. Architectural reengineering


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Typical build quality of electric guitar

• Sucks!• Component quality• Ground loops• Shielding• Electric shock


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So yeah, it sucks. So we make our own.

And all is good.

Until we realize it still sucks…...but for different reasons.


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Problem: The pickup select switch• Combinations hard-wired

Solution:• Hardwire new combinations• Add a bigger switch

What just happened?Functional vs. Architectural reengineering


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Possible configurations amongst combinations• Coil selection• Coil wiring• Coil phasing

What to do?Start working.


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Electromechanical: toggles, rotaries, pots• Need functionality? Add switches!

Pros:• Simple, at first• No added power consumption

Cons:• Heavy real-estate costs• Doesn’t scale


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Solid-state: BJTs, MOSFETs, vacuum tubes• Switches are now just logical inputs

Pros:• Simplifies architecture• Cheap

Cons:• Power required• Scales terribly


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IC: Integrated circuit• Solid-state now just does signal routing

Pros:• Black-boxing saves devel and maint time• Still cheap

Cons:• Limited by vendor supplies• Scales poorly


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MCU: MicroController Unit• ICs, if used at all, now only supplement MCU functionality

Pros:• Eliminates need for most ICs• Programmable

Cons:• High power consumption• Hurts wallet• Requires programmer


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Choose your MCU architecture wisely

• ARM: Most popular. Pure, small RISC.

• Atmel AVR: C efficient. Dedicated hobbyist following.

• Basic Stamp: Fast learning curve. Dedicated hobbyist following.

• Intel 8051: Very popular. Boolean processing engine.

• Microchip PIC: Wide supplementary software support. Dedicated hobbyist following.

• Motorola 68xx: Highly optimized. HCF instruction.

• TI: Cool calculator programs in BASIC. Dedicated hobbyist following.


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SoC: System on a Chip• Only need interface, routing, and this chip

Pros:• Entire system on a single chip• Compile hardware from software

Cons:• Very high power consumption, especially FPGA• Very hurtful on wallet, especially ASIC


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What just happened?

Layered architecture


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Software options

• Low level, e.g. assembler

• Mid level, e.g. C

• High level, e.g. OS


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Requirements

Standard• Do everything a typical electric guitar can• Built better

Configurable• Selections, wiring, phasing• Save/Recall configurations

Communications• MIDI• OSC• File transfer

Intonation• Built-in tuner• Harmonized infinite sustain


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Harmonized infinite sustain

• Strum once, sing forever

• EBow

• Fernandez


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MIDI

• Serial

• Note

• Velocity


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OSC

• Application level protocol

• Ethernet

• Wrap MIDI


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File transfer

• Internet Protocol suite: IP, ICMP, TCP, UDP, HTTP, FTP

• USB


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Embedded OSes• Pick something with requirements in mind

Examples:• AvrX - Assembly. Speed.• Contiki - C. Dynamic.• DCOS - C. Minimalist.• NutOS - C. Networking.• Salvo - C. Small.• TinyOS - Pseudo-C. Static modules.

Oh my Gosh! COTS!


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Prototype releases

• Alpha

• Beta

• Gold

Software extends hardware.Both play well together in a good system.


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ReferencesMotorola 6800. Retrieved: 2005/03/09. http://en.wikipedia.org/wiki/6800 Intel 8051. Retrieved: 2005/03/09. http://en.wikipedia.org/wiki/8051 Arm architecture. Retrieved: 2005/03/09. http://en.wikipedia.org/wiki/ARM_architecture Atmel AVR 8-Bit RISC. Retrieved: 2005/02/27. http://www.atmel.com/products/AVR/ AvrX. Retrieved: 2005/02/27. http://www.barello.net/avrx/ BASIC Stamp. Retrieved: 2005/03/09. http://en.wikipedia.org/wiki/Basic_Stamp ConfiGuitar Info Index. Retrieved: 2005/02/27. http://www.uwplatt.edu/~schaumba/configuitar/ Dunkels, Adam. The Contiki Operating System. Retrieved: 2005/02/27. http://www.sics.se/%7Eadam/contiki/ Hofmeijer, Dullman, Jansen, and Havinga. DCOS, A REAL-TIME LIGHT-WEIGHT DATA CENTRIC OPERATING SYSTEM. Retrieved: 2005/02/27. http://wwwes.cs.utwente.nl/smartsurroundings/publications/Hofmeijer04.pdf The Amazing EBow. Retrieved: 2005/02/27. http://www.ebow.com/ Electric Guitar. Retrieved: 2005/02/27. http://en.wikipedia.org/wiki/Electric_guitar Ethernet. Retrieved: 2005/02/27. http://en.wikipedia.org/wiki/Ethernet Fernandes - Sustainer Audio Demos. Retrieved: 2005/02/27. http://www.fernandesguitars.com/sustainer/susdemos.html Internet Protocol. Retrieved: 2005/02/27. http://en.wikipedia.org/wiki/Internet_Protocol Les Paul 2005. Retrieved: 2005/02/27. http://en.wikipedia.org/wiki/Les_Paul Lute. Retrieved: 2005/02/27. http://en.wikipedia.org/wiki/Lute EMUSIC-L - MIDI specification. Retrieved: 2005/02/27. http://www.ibiblio.org/pub/multimedia/emusic/info-docs-FAQs/MIDI-doc/ MIPS architecture. Retrieved: 2005/03/09. http://en.wikipedia.org/wiki/MIPS_architecture nesC: A Programming Language for Deeply Networked Systems. Retrieved: 2005/02/27. http://nescc.sourceforge.net/ Ethernut Software. Retrieved: 2005/02/27. http://www.ethernut.de/en/software.html Atchley, John. GuitarNuts.com - The Internet Home for Wayward Pickers. Retrieved: 2005/02/27. http://www.guitarnuts.com/index.php OpenSoundControl. Retrieved: 2005/02/27. http://www.cnmat.berkeley.edu/OpenSoundControl/ OpenSound Control. Retrieved: 2005/02/27. http://en.wikipedia.org/wiki/OpenSound_Control PIC microcontroller. Retrieved: 2005/03/09. http://en.wikipedia.org/wiki/PIC_microcontroller Stang, Pascal. Procyon AVRlib - C-Language Function Library for Atmel AVR Processors. Retrieved: 2005/02/27. http://hubbard.engr.scu.edu/embedded/avr/avrlib/ Point-to-Point Protocol. Retrieved: 2005/02/27. http://en.wikipedia.org/wiki/Point-to-Point_Protocol Pumpkin: Salvo, the RTOS that runs in tiny places. Retrieved: 2005/02/27. http://www.pumpkininc.com/ Han, Rengaswamy and Shea. Reconfigurable Sensor Networks with SOS. Retrieved: 2005/02/27. http://deerhound.ats.ucla.edu: 7777/pls/portal/docs/PAGE/NEWS_EVENTS/EVENTS/ 04_REVIEW_POSTERS/2ND_ANNUAL_REVIEW_POSTERS_FILES/SOS.PDF Texas Intruments. Retrieved: 2005/03/09. http://en.wikipedia.org/wiki/Texas_Instruments TinyOS Community Forum || An open-source OS for the networked sensor regime.. Retrieved: 2005/02/27. http://www.tinyos.net/ Verilog. Retrieved: 2005/03/07. http://en.wikipedia.org/wiki/Verilog


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Questions?

SE411: 2005/Mar/10, Andrew Schaumberg, Systems Engineering

Systems Engineering Andrew Schaumberg SE411: 2005/Mar/10.

Documents

2005mar10 slide

programmer slide

systems engineering

electric shock slide

microphone pickup slide

architecture cheap cons

mcu architecture

simple architecture