CS294-11 Spring 1999 Project - Palm to COTS Dust IrDA link

 

Palm to COTS Dust IrDA Link Workpad -> COTS Dust

Brett Warneke, Sunil Bhave

CS294-11:Topics in System Design for Post-PC Devices

Spring 1999

Goal:

Develop a 1 in3 self-contained device that includes various sensors and wireless communications (COTS dust) utilizing IrDA DATA so that it can communicate with the plethora of IrDA capable devices such as the Palm Computing platform, laptop computers, and other COTS dust devices.

Presentations:

  1. Sensor and Actuator Overview
  2. Spring 1999 Final Presentation

Purpose:

  1. Demonstrate wireless communication between a stock IBM Workpad and a small multi-sensor node
  2. Demonstrate an IrDA relay node to form the routers/gateways for a TCP/IP over IrDA network.  Each node would provide entry to the network by IrDA devices such as the IBM Workpad and act as a router to distribute packets throughout the network.  One or more of the nodes would connect to a IrDA dongle hanging off a networked desktop computer or an IrDA to Ethernet interface so that each device can connect to the Internet without being in proximity to a port.

Deliverables:

  1. IrDA Board 1 (one sensor, one transceiver)
    1. Schematics: Coin Cell version, 2/3A Cell version
    2. Layout
      1. Coin Cell version: 1.18" x 0.90" = 1.06 in2
      2. 2/3A Cell version: 1.68" x 0.71" = 1.19 in2
    3. Photograph of stuffed board (with temperature sensor missing)

Tasks:

  1. Select IrDA components
    1. Vishay Telefunken TFDU4100 or TFDS4500
      1. up to 115.2 kbps
      2. 1.0 mA supply current (Receive)
      3. 3.5 mA supply current (Transmit)
      4. typical 210mA transmit LED current
      5. 5nA Sleep current
      6. built-in EMI protection
      7. 3m range
      8. Samples: (2-3 weeks)
        1. ELREPCO, Inc.
        2. (650)926-0660
        3. 777 Cuesta Drive, Mountain View, CA 94040
    2. Maxim MAX3100 SPI/Microwire-Compatible UART
      1. 8-word FIFO
      2. 150µA operating current
      3. 10µA current in shutdown
      4. 16-pin QSOP package
  2. Design PCBs
    1. PCB prototypes from Alberta Printed Circuits, Proto 1 service
    2. basic relay PCB - five transceivers (each edge of the board plus the top) and one sensor (temperature or light)
    3. sensor PCB - five transceivers and >6 sensors
      1. Analog DevicesAD7814 10-Bit Digital Temperature Sensor
        1. Resolution: 0.25°C
        2. Accuracy: ±2°C
        3. 6 lead SOT-23 package
        4. 250µA in normal mode
        5. 1µA in shutdown mode
        6. SPI interface - 10MHz max serial clock
        7. Samples:
          1. not available from distributors yet
          2. Analog Devices Customer Service: (800)262-5645, Lee Johnson, before 3:30pm PDT
      2. Crystal Oscillator options:
        1. If use oscillator, only need one for both microcontroller and UART
        2. If use crystals, need one for the microcontroller and another for the UART, but can then power down the oscillator
        3. Epson MC-405 surface mount quartz crystal, 32.768kHz (RTC/sleep counter), Digi-Key page 245
        4. ECS Inc. ECX-306 SMT quartz crystal, 32.768kHz (smaller than MC-405), Digi-Key page 249
        5. ECS Inc. CSM-12 surface mount crystal, 3.6864MHz, Digi-Key page 252
        6. ECS Inc. through hole crystal, 1.8432MHz, Digi-Key page 250
        7. Epson SG636PCE/636PCV Oscillator, 3.2768 MHz (115.2 kbs), Digi-Key page 243
          1. Output enable
          2. 9mA max
          3. measured a 5V 1MHz crystal at 3V, room temperature - 0.75mA
        8. ECS Inc. ECS-8FM Oscillator, 1.8432 MHz (57.6 kbs), Digi-Key page 252
      3. Switch transistor for transceiver shutdown: Zetez FMMT3906 PNP, Digi-Key page 208
      4. Switch:
        1. CTS SMT Half Pitch DIP Switches, Digi-Key p. 423 (CT2182LPST-ND)
        2. C&K Components GT series toggle switch, Allied p. 234
        3. E-Switch EG1270 slide switch, Digi-Key page 417
      5. Resistors:
        1. Panasonic 0402: SM, 5%, 1/16W, 1x0.5mm, Digi-Key p. 354
        2. Panasonic 2512: SM, 1%, 1W, 6.4x3.2mm, Digi-Key p. 354
      6. Capacitors: Panasonic Ceramic Chip Capacitors 0402, 0603, Digi-Key p. 340
      7. Connector: Waldom molex micro-miniature 1.25mm, 9.25x3.2mm, Digi-Key p. 52 (SM Header: WM1768-ND)
      8. LED: LITEON Optoelectronics, 0603 SOT-23, red, Digi-Key p. 576
      9. Batteries: battery choice set by max current drain for transmit LED
        1. First case: coin cell with 15mA max drain; use capacitor to provide higher drain
          1. assumptions: equal probability of '1' or '0'
          2. (1/2 probability of driving the LED) * 1/(9600 bps) * (3/16 duty cycle) * (0.21 A for the LED) = 2.1µC per bit
          3. (10 bits per word) * ((16 control words + up to 64 payload words) per frame) * 2.1µC per bit = 1.6mC per frame
          4. 1.6mC per frame / 3V = 547µF storage capacitor
          5. Panasonic VS Aluminum Electrolytic Capacitor, Surface Mount: 4V, 1000µF, 63µA max leakage current, 2000 Hour Life at 85°C, Digi-Key page 315
          6. Panasonic Lithium Coin Cell, 210 mAh, 15mA max drain, 0.2 mA standard drain, 20x3.2mm, Digi-Key page 496
          7. Memory Protection Devices, PC Mount Coin Cell Holder, Digi-Key page 499 (BH800)
          8. measured the average LED current for an HSDL 1001 transmitting at 2400bps and about 10 words/sec: 0.55mA
        2. Second case: larger battery that can provide the large drain
          1. Panasonic Lithium 2/3A, 1200 mAh, 17x33.5mm, 250mA max drain, 2.5mA standard drain, Digi-Key page 496
          2. Memory Protection Devices, PC Mount Low Profile 2/3A Cell Holder, Digi-Key page 499 (BC 2/3AE)
      10. Atmel AT90LS8535 8-bit AVR Microcontroller
        1. 8KB in-system programmable flash
        2. 512 bytes EEPROM
        3. 512 bytes SRAM
        4. 8 Channel 10-bit ADC
        5. UART
        6. 0-4MHz clock
        7. analog comparator
        8. 2.7-6.0V operation
        9. SPI interface - fclock/4 max
        10. 44 pin TSOP package
        11. Power at 4 MHz, 3V
          1. Active: 5mA
          2. Idle (CPU stopped, all peripherals on): 3mA
          3. Power Down (oscillator stopped, only external interrupts or reset (WDT or external) wake up the MCU), WDT enabled: 15µA
          4. Power Down (oscillator stopped, only external interrupts or reset wake up the MCU), WDT disabled: 5µA
          5. Power Save (same as Power Down, except asynchronous Timer/Counter2 still runs and can wake the MCU), WDT disabled: 15µA
  3. Atmel AVR microcontroller coding
    1. Imagecraft AVR C compiler
    2. Implement the IrDA protocol stack on the Atmel AVR
    3. Write code to sample the sensors and send the data immediately to the Workpad
    4. Write code to sample the sensors, store the data with a timestamp, and send the stored data to the Workpad upon command
    5. Write relay code
    6. Extend relay code to provide routing
  4. Palm Computing Platform coding
    1. Program to grab data from the sensor mote and display it
    2. Extend above program to plot the data
    3. Extend above program to grab selected stored data and plot it
  5. Deliverables (at least 1 and 2 this semester)
    1. Workpad acquiring data from a single mote
    2. A single Workpad using a relay mote (one or more) to connect with the IrDA dongle on a PC with a TCP/IP connection
    3. Workpad acquiring data from a network of motes
    4. Multiple Workpads communicating with each other and a PC over a network of relay motes
    5. Extend the last point to allow the Workpads to get data from the sensors embedded in the network

References

Palm Computing and IrDA

IrDA

Interesting Projects and Products


Brett Warneke, October 28, 1999

Brett Warneke - last edited July 25, 2000