1 TinyOS Mohammad Rahimi CSCI599-Spring2002

2 Motivation  The new class of distributed tiny devices  The new generation of software

3 Characteristic  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

4 PDA Keys Headphones Pen (Anoto) Display Watch Health Monitor Hearing aid Authentication Ring Fixed Infrastructure

5 Dot Mote

6 Rene Mote

7 Hardware  4Mhz, 8bit MCU (ATMEL) 512 bytes RAM, 8K ROM  900Mhz Radio RF Monolithic ft. range  Temperature Sensor  Light Sensor  LED outputs  Serial Port 5mA Active and 5uA sleep

8 A Modular Approach  Components –Wired together –Interface may join different components  Program is Execution Graph & scheduler

9 Component  Component interface –Commands that it accepts –Events that it signals –Commands that it uses –Events that it handles  Component Frame –Maintain internal state  Event –Initiate at lowest level by hardware –Make a FSM model  Task –Tasks: internal concurrency –Non Preemptive Messaging Component Internal State Internal Tasks CommandsEvents SynchronousAsynchronous

10 scheduler 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

11 Application  Application = graph of components + scheduler RFM Radio byte i2c Temp photo Messaging Layer clocks bit byte packet Radio Packet Routing Layer sensing application application HW SW ADC messaging routing UART Packet UART byte

12 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); };

13 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 ……..

14 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 !

15 Communication Application Dynamic Network Discovery Ad hoc multi hop routing Detail of Implement Low Power Little storage Active Message layer

16 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

17 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

18 FUN!  29 Palms Fixed/Mobile Experiment

19 Cool 6

20 Fun Again Largest Tiny Network Yet Large-Scale Demonstration of Self-Organizing Wireless Sensor Networks

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22 Links    

23 END!