Microchip dsPIC Microchip dsPIC Digital Signal Digital Signal ControllersControllers

Senior Design Project 2005Senior Design Project 2005

Super-Mileage Fuel Injection Super-Mileage Fuel Injection TeamTeam

Micro-Controllers In Our Project Micro-Controllers In Our Project (I)(I)

We will require a primary processor to We will require a primary processor to implement our feedback control system.implement our feedback control system.

It will need to have a timed logical output It will need to have a timed logical output triggered by a system interrupt of our choice.triggered by a system interrupt of our choice.

It will need to perform certain math It will need to perform certain math operations in hardware and with few operations in hardware and with few instructions.instructions.

Development Options must include high level Development Options must include high level language compilers.language compilers.

Programming options must include a Programming options must include a portable PC-Controlled Option.portable PC-Controlled Option.

Micro-Controllers In Our Project Micro-Controllers In Our Project (II)(II)

We will also require a microcontroller We will also require a microcontroller to control a data storage and to control a data storage and retrieval scheme.retrieval scheme.

It must have a sufficient number of It must have a sufficient number of output pins to send and receive data output pins to send and receive data from memory as well as address a from memory as well as address a virtual memory space of our chosen virtual memory space of our chosen size.size.

What are the Options?What are the Options? Feedback Control SystemFeedback Control System

– Motorola DSP56xxx seriesMotorola DSP56xxx series– Microchip dsPIC seriesMicrochip dsPIC series– Amtel, Analog Devices, OthersAmtel, Analog Devices, Others

Why DSP anyway? Benefits? Pitfalls?Why DSP anyway? Benefits? Pitfalls?– Higher operand bit count, greater precision in calculationsHigher operand bit count, greater precision in calculations– Does the math operations of interest in a single Does the math operations of interest in a single

instructioninstruction– Higher potential clock speedHigher potential clock speed– C Compilers AvailableC Compilers Available– Might require us to purchase some new programming Might require us to purchase some new programming

hardwarehardware

What if we used a lower end What if we used a lower end controller?controller?

Microchip 16 and 18 series as exampleMicrochip 16 and 18 series as example-No implementation of certain math apps-No implementation of certain math apps-Higher level language use is more limited-Higher level language use is more limited-Iterative calculation strategy-Iterative calculation strategy-Limited Program Memory-Limited Program Memory

However, 16/18 series or equivalent will be However, 16/18 series or equivalent will be adequate for our sensor data recording systemadequate for our sensor data recording system– Only needs to implement data collection, storage, Only needs to implement data collection, storage,

retrieval, and download to a PC via a serial connectionretrieval, and download to a PC via a serial connection

The PitchThe Pitch

The Front Runner: Microchip dsPIC seriesThe Front Runner: Microchip dsPIC series-Three families: Electronic Motor -Three families: Electronic Motor Control, Sensor Family, General Purpose Control, Sensor Family, General Purpose FamilyFamily

BenefitsBenefits– Uses the same assembly language we are all Uses the same assembly language we are all

familiar with from undergrad coursesfamiliar with from undergrad courses– Implements necessary mathImplements necessary math– One-shot PWM with interrupt triggeringOne-shot PWM with interrupt triggering– In-Circuit-Serial-ProgrammingIn-Circuit-Serial-Programming