Transcript TinyOS - USC Robotics Research Lab

TinyOS
Mohammad Rahimi
CSCI599-Spring2002
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Motivation
 The new class of
distributed tiny
devices
 The new generation
of software
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Characteristic

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Highly distributed
Dynamic and Self Organizing
Communication centric
Adaptive
Concurrency intensive
– Sudden burst of network activity and sleep
 General Purpose
– As opposed to traditional tailor made system
programming
 Not only control oriented anymore
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Hearing aid
Headphones
Fixed
Infrastructure
PDA
Pen (Anoto)
Health Monitor
Authentication
Ring
Display Watch
Keys
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Dot Mote
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Rene Mote
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Hardware
 4Mhz, 8bit MCU (ATMEL)
512 bytes RAM,
8K ROM
 900Mhz Radio
RF Monolithic
10-100 ft. range
 Temperature Sensor
 Light Sensor
 LED outputs
 Serial Port
5mA Active and 5uA sleep
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A Modular Approach
 Components
– Wired together
– Interface may join different components
 Program is Execution Graph & scheduler
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Component
Synchronous Asynchronous
 Component interface
Messaging Component
– Commands that it accepts
Internal State
Internal Tasks
– Events that it signals
– Commands that it uses
– Events that it handles
Commands
Events
 Component Frame
– Maintain internal state
 Event
– Initiate at lowest level by hardware
– Make a FSM model
 Task
– Tasks: internal concurrency
– Non Preemptive
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scheduler
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Shared stack, static frames
Events preempt tasks, tasks do not
Events can signal events or call commands
Commands don’t signal events
Either can post tasks
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Application
 Application = graph of components + scheduler
sensing application
application
Routing Layer
routing
Messaging Layer
messaging
packet
byte
bit
Radio Packet
UART Packet
Radio byte
UART byte
RFM
photo
clocks
ADC
Temp
SW
i2c
HW
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Component Definition
TOS_MODULE PHOTO;
ACCEPTS{
char PHOTO_INIT(void);
char PHOTO_GET_DATA(void);
char PHOTO_PWR(char mode);
};
SIGNALS{
char PHOTO_DATA_READY(int data);
};
USES{
char SUB_ADC_INIT(void);
char SUB_ADC_GET_DATA(char port);
};
HANDLES{
char PHOTO_ADC_DONE(int data);
};
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Description
include modules{
MAIN;
SENS_OUTPUT;
INT_TO_LEDS;
CLOCK;
PHOTO;
};
MAIN:MAIN_SUB_INIT SENS_OUTPUT:SENS_OUTPUT_INIT
MAIN:MAIN_SUB_START SENS_OUTPUT:SENS_OUTPUT_START
SENS_OUTPUT:SENS_OUTPUT_CLOCK_EVENT CLOCK:CLOCK_FIRE_EVENT
SENS_OUTPUT:SENS_OUTPUT_SUB_CLOCK_INIT CLOCK:CLOCK_INIT
SENS_OUTPUT:SENS_OUTPUT_SUB_OUTPUT_INIT INT_TO_LEDS:INT_TO_LEDS_INIT
SENS_OUTPUT:SENS_OUTPUT_OUTPUT_COMPLETE INT_TO_LEDS:INT_TO_LEDS_DONE
SENS_OUTPUT:SENS_OUTPUT_OUTPUT INT_TO_LEDS:INT_TO_LEDS_OUTPUT
SENS_OUTPUT:SENS_DATA_INIT PHOTO:PHOTO_INIT
SENS_OUTPUT:SENS_GET_DATA PHOTO:PHOTO_GET_DATA
SENS_OUTPUT:SENS_DATA_READY PHOTO:PHOTO_DATA_READY
……..
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Communication
 Active messaging
– The name of on the handler on the target
– Payload to pass as argument (data)
– Transmit
– Acknowledge
 It looks like a light weight RPC !
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Communication
Application
Dynamic Network Discovery
Ad hoc multi hop routing
Active
Message layer
Detail of Implement
Low Power
Little storage
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Challenges
 Tight memory
– Although Each component has its own stack
communication messages pass by changing
ownership
 Adaptive and dynamic
– Code migration
 direct connection of micro controller to
physical layer
– Event driven model
 Low Power
– Sleep at two different granularity
– Low granularity maintain the original capacity
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Network Discovery and
Ad hoc routing
 Root with ID Zero advertise
 Nodes select the lowest ID they hear as
Parent
 To route a node determines its parent as
multi hop forwarding handler
 Optimizations
– Clustering
– Piggy backing
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FUN!
 29 Palms Fixed/Mobile Experiment
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Cool
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Fun Again
•Largest Tiny Network Yet
•Large-Scale Demonstration of Self-Organizing
Wireless Sensor Networks
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Links
 http://today.cs.berkeley.edu/800demo/
 http://tinyos.millennium.berkeley.edu/29Palms.htm
 http://tinyos.millennium.berkeley.edu/#demos
 http://today.cs.berkeley.edu/tos/
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END!
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