© 2003 NVision Technologies NVision Technologies presents… NVision Technologies: Jozsef Dudas, Seema Jaffer, Deanna Lee, and Byron Thom ENSC 340 Presentation:

© 2003 NVision Technologies

NVision Technologies presents…

NVision Technologies:Jozsef Dudas, Seema Jaffer, Deanna Lee, and Byron Thom

ENSC 340 Presentation: December 18, 2003

an Automotive Diagnostic Tool


Overview

Meet the TeamMeet the Tool

Yesterday Today Tomorrow

Wrap-up


Meet the Team

NVision Technologies Group Leader and Hardware Lead

Jozsef Dudas

Firmware Co-Leads Seema Jaffer, Deanna Lee

Software Lead Byron Thom


Meet the Tool: Overview

Its purpose and marketIts marketabilityIts technical aspectsIts management


Meet the Tool

Problem GM hobbyists needed a tuning tool

Tool interfaces with car’s computer

Current Solutions Commercial Scan tools ($300 USD) Manufacturer Tools ($10,000 USD)

Our Solution Low-cost per function…


Meet our Tool

Low-cost Software-defined and upgradeable Full SAE compliance in a single box

Upgradeable features Accommodates user-defined add-on functions Easy incorporation of future standards

Programming the automobile computer


The Tool: Marketability

Market Potential Growing “Import-tuner” market

Car hobbyists Accessorizers

GM knows it’s importantProduction Cost

Software is inexpensiveSuggested Retail Price

Current cheapest tool: $200 Flexible


System Overview


The Tool: Operation’s Concept

User: requests specific sensor data iPaq: passes data request to car via cable Cable: repackages request and sends it to the car Cable: receives data and repackages it for iPaq iPaq: receives data and displays it for the user


The Tool: Technical Aspects

Composed of: Hardware

Platform for firmware and software

Firmware the Translator Cable control between the car

computer and the iPaq

Software the iPaq graphical user interface and control


The Tool: Hardware

Parts ProcurementCable Hardware

OBD-II Connector, uC, Transceivers, Boards, Connectors, etc.

Board for robustness Transceiver chip for simplicity

Ipaq Versatile, fast, cheap, and sexy!

Test PCM


The Tool: Hardware Challenges

Programming the PIC Homebrew programmer blew up Microchip ICD didn’t work Required board rework

Most things actually worked!


The Tool: Firmware

Bridge between iPaq and PCMTransparent (standalone)Real-time Interrupt-driven hierarchyWritten in C (instead of assembly)

Portability Easy to read


The Tool: Firmware Challenges

Simulation and Debugging Challenging to obtain debugging information Initially unfamiliar with PIC

Timing (real-time system) Problem

not enough time Solution:

Nested-interrupts Optimized code


The Tool: Firmware Status

What works Simulation (logic) of firmware

What doesn’t Timing issues prevail I/O (firmware running on hardware)


The Tool: Software App Layer

iPaq 3165 PDA Pocket PC 2002

J2190/J2178 SAE StandardsSerial Communications (RS-232)Graphical User Interface


The Tool: Software App Layer

Small Screen Displays Gauge and Digital Displays

Scalability Power of J2190 Sensors and PIDs

Speed

KPH


The Tool: Budget

Budget Predicted Total: $ 492.00 Actual Total: $1006.07 Difference: $ 514.07

Summary:

WE HAVE OVERSPENT!


The Tool: Budget

But not really…

Total Cost: $1006.07 NSERC: $ 250.00 ESSEF: $ 200.00 Wighton (SAE Docs): $ 572.65 Net Amount: -$ 16.58

We are making a profit of $17!


The Tool: Schedule

Hardware:

Firmware:

Software:

System Integration:

Predicted Completion Dates

October 10

October 27

November 12

December 4

Actual Completion Dates

October 15

December 4

December 1

December 17


The Tool: Tomorrow

A lot of room for future developmentHardware

Integrate various other standards Miniaturize

Firmware Fully robust Run on a faster (available) chip Support all four communication methods


The Tool: Tomorrow

Software Other Operating Systems

Palm, Cell Phones

Diagnostic Purposes Engine Light, Maintenance Required

Parameter Modifications Timing and Efficiency


Team Summary

Lessons LearnedConclusionsAcknowledgements


Lessons Learned

Mike Sjoerdsma was rightHaving the standards at the beginning is

important“Doing it right” doesn’t always get the job

done!Sometimes numerous revisions are

needed to meet requirements


Lessons Learned

Murphy was right.Lots of problems won’t flow to the surface

until you start implementing.. And integrating

“Timing” is a big dealWin CE != Win 2KSAE standards were written by engineers


Conclusions

It’s a good ideaIt’s a good productWe almost got it workingThis product could make money


Acknowledgements

Andrew, Steve, the TA’s, and FredJoe’s Mom Our Teammates


Any Questions?


Demonstration


Hardware

iPaq Small Portable

board Reliable Miniaturized for final version


iPaq Software

GUI (demonstrate Dial Digital display Editing sensor data request

J2190 SAE Standard Flexibility Convoluted SAE compliance provides future scalability

Serial Multi-threading to meet real-time requirements


Firmware: High Level

Serial (to/from iPaq)J1850 (to/from PCM)

PIC (Firmware)

PhysicalReception &

MemoryAllocation

PhysicalTransmission

Decode last bitand shift into

register

Encode next bitand shift into

register

DecodeAddress,

check CRC

Generate CRC

J1850(PCM)

PhysicalTransmission

PhysicalReception &

MemoryAllocation

iPaq

Serial (RS232 to iPaq) J1850 (to PCM)


Firmware: Low Level

PIC Firmware

J1850 Module (communicates with PCM)

Transmission/Arbitration

J1850TxBit

RS 232 Module (communicates withiPaq)

UART

Reception

FSMShift

RegisterTiming

Main Program

J1850(PCM)

RS232(iPaq) J1850Tx

CRC BufferArbitration

J1850RxBit

FSMShift

RegisterTiming

J1850Rx

EncodeAddress

CRC Buffer

DecodeCommand

Decoder/Interpreter

Buffer(Write)

Buffer(Read)

Legend

Subroutine called in main ProgramInterrupt subroutine (I/O)Block of code (i.e. CRC)Architectural Block (i.e. Tx)Sub-Module within PIC firmwareSub-system (i.e. PIC, iPaq, etc.)


Firmware: Simulation

Simulation (on manufacturer software) Useful to test logic Can mimic I/O to some extent

What works (everything) Transmission and reception memory management CRC generation/checking


Firmware: H/W Debugging

PIC (Firmware)iPaq (Software)

Receive(from PCM)

GUI

Transmit(to iPaq)

Transmit(to PCM)

Receive(from iPaq)

Loopback


Firmware: H/W Debugging

Hardware debugging Loop-back mode

What works Transmits (to PCM in loop-back) correctly Receive-interrupt issues Timing issues

Not enough time to receive (the transmission)


Any Questions?

Documents

© 2003 NVision Technologies NVision Technologies presents… NVision Technologies: Jozsef Dudas, Seema Jaffer, Deanna Lee, and Byron Thom ENSC 340 Presentation: