RaPTEX: Rapid Prototyping of Embedded Communication Systems Dr. Alex Dean & Dr. Mihai Sichitiu (ECE) Dr. Tom Wolcott (MEAS) Motivation  Existing work in customizable communication systems focuses on X-over-Ethernet for workstations  Vast range of applications can’t use this  Large potential payoff for applying advanced, integrated compiler + scheduler optimizations in domain-specific software patterns Center for Embedded Systems Research Protocol Specification GUI Input Communication Library Source Code User Protocol Communication Source Code Application Specification GUI Input Application Library Source Code Smart Node Closed Loop Ctlr. Input Monitor Data Logger Bridge Node Interfaces UART Handshake Parallel DMA Parallel Executive Functions Transmit Functions Receive Functions Other Protocol Functions C Source Code Executive Functions Transmit Functions Receive Functions Other Protocol Functions Assembly Code Thrint Minimum CPU speed Maximum bit rate Memory Size Information ROM RAM Power Models MCU Peripherals Transceiver CPU % for 2 ary threads during send receive idle Parameterized Power and Energy Consumption, Battery Life size Thread Integrator Int. Executive Functions Int. Transmit Functions Int. Receive Functions Other Int. Protocol Functions Executable Application Functions User Application Source Code GCC GCC (as/ld) Power Analysis Send Message Receive Message Idle Analysis Information Code Flow User-Derived Specifications Integrated Assembly Code Timing Analysis Send Message Receive Message Idle Co-Simulator/ Debugger Target Hardware GUI Output Project Goals  Develop tool to enable quick development of embedded communication systems  Select & customize protocol and application “building blocks”  Efficiently merge blocks using advanced compiler optimizations (including software thread integration) and lightweight task scheduler  Statically calculate node-level requirements (energy, cycles, clock speed, memory)  Estimate system-level performance through simulation  Create library for specialists and non-specialists  Protocol and application building blocks  Turn-key applications  Hardware reference platforms  Demonstrate systems in two domains  Wireless sensor networks for structural health monitoring  Underwater ultrasonic biotelemetry Underwater Ultrasonic Comm.  Adverse medium  Multipath interference introduces echoes, frequency nulls  Noise from surf, motors, etc.  Ultrasonic transducer operates at 50 kHz – 80 kHz  Use Multi-Carrier Modulation  Carriers at 55, 60, 65, 70, 75 kHz  Limited resources  Small size and weight – must ride on crab  Limited energy  Limited compute power  Drive with overclocked 8-bit microcontroller PollingAlohaCSMA/* OFDM Ultrasonic Transducer RF Transceiver MAC Modulation Logical Link Control Application Beacon Telemetry Datalogger? ? Network ? Medium Real-Time Guest (Primary) Thread Hardware Function Host (Secondary) Thread Idle Time Integrated Thread Guest Schedule (Execution Time Reqts.) Idle Time Reclaimed Software Thread Integration Execution Time Visualization Receiver Field Data Capture Unit Analog Channel Simulator Avrora AVR Microcontroller Simulator Data Logging Ultrasonic Sensor or Radio Receiver PC Ultrasonic Transducer Performance Received Ultrasonic Pulse (Multipath Interference)