Microchip Technology PICDEM™ Mechatronics Demonstration Board User’s Guide

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PICDEM™ Mechatronics

Demonstration Board

User’s Guide

Note the following details of the code protection feature on Microchip devices:

• Microchip products meet the specification contained in their particular Microchip Data Sheet.

• Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the intended manner and under normal conditions.

• There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data Sheets. Most likely, the person doing so is engaged in theft of intellectual property.

• Microchip is willing to work with the customer who is concerned about the integrity of their code.

• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not mean that we are guaranteeing the product as “unbreakable.”

Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our products. Attempts to break Microchip’s code protection feature may be a violation of the Digit al Millennium Copyright Act. If suc h a c t s allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.

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Trademarks

The Microchip name and logo, the Microchip logo, Accuron, dsPIC, K

EELOQ, microID, MPLAB, PIC, PICmicro, PICSTART,

PRO MATE, PowerSmart, rfPIC and SmartShunt are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.

AmpLab, FilterLab, Migratable Memory, MXDEV, MXLAB, SEEVAL, SmartSensor and The Embedded Control Solutions Company are registered trademarks of Microchip Technology Incorporated in the U.S.A.

Analog-for-the-Digital Age, Application Maestro, CodeGuard, dsPICDEM, dsPICDEM.net, dsPICworks, ECAN, ECONOMONITOR, FanSense, FlexROM, fuzzyLAB, In-Circuit Serial Programming, ICSP, ICEPIC, Linear Active Thermistor, Mindi, MiWi, MPASM, MPLIB, MPLINK, PICkit, PICDEM, PICDEM.net, PICLAB, PICtail, PowerCal, PowerInfo, PowerMate, PowerTool, REAL ICE, rfLAB, rfPICDEM, Select Mode, Smart Serial, SmartT el, Total Endurance, UNI/O, WiperLock and ZENA are trademarks of Microchip Technology I ncorporat ed in the U.S.A. and other countries.

SQTP is a service mark of Microchip Technology Incorporated in the U.S.A.

All other trademarks mentioned herein are property of their respective companies.

Printed on recycled paper.

Microchip received ISO/TS-16949:2002 certification for its worldwide headquarters, design and wafer fabrication facilities in Chandler and Tempe, Arizona, Gresham, Oregon and Mountain View, California. The Company’s quality system processes and procedures are for its PICmicro EEPROMs, microperipherals, nonvolatile memory and analog products. In addition, Microchip’s quality system for the design and manufacture of development systems is ISO 9001:2000 certified.

8-bit MCUs, KEELOQ

code hopping devices, Serial

PICDEMTM MECHATRONICS

DEMO BOARD USER’S GUIDE

Table of Contents

Preface ........................................................................................................................... 1

Chapter 1. PICDEM™ Mechatronics

1.1 Introduction .....................................................................................................7

1.2 Highlight s ......... ............. .. .. ........................... .. .. ........................... .. .. ................ 7

1.3 Quick Star t G u id e .................... .. ..................................................................... 8

1.4 PICDEM™ Mechatronics Development Kit Contents ...................................10

1.5 PICDEM™ Mechatronics Layout ..................................................................10

1.6 Required Tools .............................................................................................12

1.7 PICDEM™ Mechatronics Setup ...................................................................12

1.7.1 Jumper Settings ........................................................................................12

1.7.2 Board Power-Up ........................................................................................12

1.8 General PICDEM™ Mechatronics Demonstration Board Information ..........14

1.8.1 Experimentation ........................................................................................14

1.8.2 On-Board Status LEDs ..............................................................................14

1.8.3 Over-Current Protection Circuit ................................................................. 15

1.8.4 Motor Connection ...................................................................................... 15

1.8.5 Serial Communication ............................................................................... 15

1.8.6 Snap-Off Sensors ...................................................................................... 16

1.8.7 Back EMF Scaling Resistors ....................... ....................................... ....... 16

1.8.8 Current Sense ...........................................................................................16

1.8.9 Header/Jumper Functions ......................................................................... 17

Chapter 2. Example Projects

2.1 Introduction ...................................................................................................19

2.2 Loading Projects in MPLAB

2.3 Example Pr o je c ts ........... .. ........................... .. .. .............. .. .. ............. .. ... ......... 20

2.3.1 Project 1: Hello World (Light a LED) ....................................................................... 21

2.3.2 Project 2: Dusk Indicator Using the Voltage Comparator ........................................ 23

2.3.3 Project 3: Thermometer Using the Analog-to-Digital Converter ..............................25

2.3.4 Project 4: Digital Clock Using Timer1 .....................................................................27

2.3.5 Project 5: Brushed DC Motor Speed Control with Optical Encoder Feedback ....... 29

2.3.6 Project 6: Brushed DC Speed Control with Back EMF Feedback ..........................32

2.3.7 Project 7: Stepper Motor Control: Single Stepping, Half Stepping and

Microstepping ..................................................................................................... 35

2.3.8 Project 8: PC Interface Using the USART ..............................................................39

2.3.9 Project 9: Brushed DC Motor Control Using the ECCP ..........................................42

Chapter 3. Troubleshooting

3.1 Introduction ...................................................................................................47

3.2 Common Pr o b le m s ......... .................................................................. ... .. ....... 47

3.2.1 VDD Is Below 5V ........................................................................................47

3.2.2 No Voltage On Drive Stage .......................................................................47

IDE ................................................................. 20

PICDEMTM Mechatronics Demo Board User’s Guide

3.2.3 FAULT LED Stays On Or Continues To Trip When SW5 Is Pressed ........47

3.2.4 Microcontroller Does Not Run After Programming By The MPLAB

ICD 2 ......................................................................................................48

3.2.5 Back EMF At J16 Is Floating ......................................................................48

3.2.6 Board Is Non-Functional When Microcontrollers Are Installed In Both

U1 And U2 .............................................................................................48

3.2.7 Optical Interrupter Is Not Providing The Expected Feedback ....................48

3.2.8 Serial Communication Does Not Appear To Be Working ..........................48

Appendix A. Hardware Schematics

A.1 Introduction ..................................................................................................49

Appendix B. LCD Segment Mapping Worksheet

B.1 Introduction ..................................................................................................57

Worldwide Sales and Service .....................................................................................60

PICDEMTM MECHATRONICS

DEMO BOARD USER’S GUIDE

Preface

NOTICE TO CUSTOMERS

All documentation becomes dated, and this manual is no exception. Microchip tools and documentation are constantly evolving to meet customer needs, so some actual dialogs and/or tool descriptions may differ from those in this document. Please refer to our web site (www.microchip.com) to obtain the latest documentation available.

Documents are identified with a “DS” number. This number is located on the bottom of each page, in front of the page number. The numbering convention for the DS number is “DSXXXXXA”, where “XXXXX” is the document number and “A” is the revision level of the document.

For the most up-to-date information on development tools, see the MPLAB Select the Help menu, and then Topics to open a list of available on-line help files.

INTRODUCTION

IDE on-line help.

This chapter contains general information about this user’s guide and customer support that will be useful prior to using the PICDEM™ Mechatronics development kit. Items discussed in this chapter are:

• Document Layout

• Conventions Used in this Guide

• Warranty Registration

• Recommended Reading

• The Microchip Web Site

• Development Systems Customer Notification Service

• Customer Support

• Document Revision History

• Troubleshooting

PICDEMTM Mechatronics Demo Board User’s Guide

DOCUMENT LAYOUT

This document describes how to use the PICDEM™ Mechatronics Demonstration Board. The manual layout is as follows:

• Chapter 1: PICDEM Mechatronics – An overview of the PICDEM Mechatronics Demo Board. PCB layout, parts and how to connect the provided jumper wires to the board.

• Chapter 2: Example Projects – Projects that describe how to read the sensors on the board, drive the LCD and control several motors. These motors include a Brushed DC (BDC) motor and a bipolar stepper motor.

• Chapter 3: Troubleshooting – Provides resolutions for solving common problems associated with using the PICDEM Mechatronics Demo Board.

• Appendix A: Hardware Schematics – Illustrates the PICDEM Mechatronics Demo Board hardware schematic diagrams.

• Appendix B: LCD Segment Mapping Worksheet – Provides the LCD Segment Mapping Worksheet.

CONVENTIONS USED IN THIS GUIDE

This manual uses the following docum entat io n conven tion s:

DOCUMENTATION CONVENTIONS

Description Represents Examples

Code (Courier font):

Plain characters Sample code

Filenames and paths Angle brackets: < > Variables <label>, <exp> Square brackets [ ] Optional arguments MPASMWIN [main.asm] Curly brackets and pipe

character: { | } Lowercase characters i n

quotes Ellipses... Used to imply (but not show) addi-

0xnnn A hexadecimal number where n is a

Italic characters A variable argument; it can be either a

Interface (Arial font):

Underlined, italic text with right arrow

Bold characters A window or dialog button to click OK, Cancel Characters in angle

brackets < >

Documents (Arial font):

Italic characters Referenced books “MPLAB

Choice of mutually exclusive argu-

ments; An OR selection

Type of data “filename”

tional text that is not relevant to the

example

hexadecimal digit

type of data (in lowercase characters)

or a specific example (in uppercase

characters).

A menu selection from the menu bar File > Save

A key on the keyboard <Tab>, <Ctrl-C>

Preface

#define START c:\autoexec.bat

errorlevel {0|1}

list

“list_option...,

[

“list_option”]

0xFFFF, 0x007A

char isascii (char, ch);

IDE User’s

Guide”

PICDEMTM Mechatronics Demo Board User’s Guide

WARRANTY REGISTRATION

Please complete the enclosed Warranty Registration Card and mail it promptly. Sending in your Warranty Registration Card entitles you to receive new product updates. Interim software releases are available at the Microchip web site.

1.1 INTRODUCTION

The PICDEM™ Mechatronics is intended to be a learning tool for individuals interested in Mechatronic design. Mechatronics refers to integrating electronic controls into mechanical systems or replacing mechanical components with an electronic solution.

PICmicro size, high efficiency, speed and abundance of peripheral configurations. Mechatronic systems range in complexity from a simple electromechanical switch with output multiplexing to the complex stabilizer control of a supersonic jet. The appliance and automotive markets are notable markets in which mechatronic designs are becoming more common place. The modern washing machine, for instance, once an entirely mechanical design, incorporates microcontrollers to manage cycle times, read human inputs and regulate the speed of the agitate and spin cycles.

This chapter introduces the PICDEM™ Mechatronics development board. It describes the PCB layout, parts and electrical connection to the PICkit™ 2 Flash Programmer and MPLAB ICD 2 In-Circuit Debugger.

PICDEMTM MECHATRONICS

DEMO BOARD USER’S GUIDE

microcontrollers are ideal for use in Mechatronic systems due to their small

1.2 HIGHLIGHTS

This chapter discusses:

• Quick Start Guide

• The PICDEM™ Mechatronics Development Kit Contents

• The PICDEM™ Mechatronics Layout

• Required Tools

• PICDEM™ Mechatronics Setup

• General PICDEM™ Mechatronics Information

PICDEMTM Mechatronics Demo Board User’s Guide

1.3 QUICK START GUIDE

The PICDEM Mechatronics Demo Board is programmed at the factory with a demonstration program. The board must be configured as described in this chapter in order to use the demonstration program. Once the board is configured and powered up, the speed of the Brushed DC (BDC) motor on the board may be varied using the potentiometer (POT1). The 8-bit hexadecimal interpretation of the position of POT1 is displayed on the LCD.

Board Setup

Using the provided wire jumpers, screwdriver and shunts (2-pin black hard plastic jumpers), configure the board as shown in Figure 1-1.

1. Attach the leads of the Brushed DC motor to Drive 1 and Drive 2 using the screwdriver.

2. Connect POT1 (on J4) to C1- (on J13) using a wire jumper.

3. Connect P1 (on J1) to RD7 (on J10) using a wire jumper.

4. Connect N2 (on J1) to RD2 (on J10) using a wire jumper.

5. Connect the right and center pins on JP8 using a shunt.

Board Power-Up

Supply power to the board in one of the following ways:

• Connect a 9-12 V

terminals.

• Connect a 9 V

• Connect a 5 V

Note:

The power supply part number is AC162039 (see buy.microchip.com). Packaged with the MPLAB ICD 2, the part number is DV164007.

DC (0.75 amp minimum) supply using J9 (see note below) DC (0.75 amp minimum) supply to the P21 and P20 screw

DC battery to the battery connector. DC (1.2 amp minimum) supply to TP2 or TP3.

Demonstration Program

Press CLR FAULT (SW5), which is near the bottom right corner of the board. Turn POT1 clockwise to increase the speed of the motor. Note that the number displayed on the LCD increases as you turn the potentiometer clockwise.

Try experimenting with the other sensors on the board:

• Move the jumper wire on POT1 (J4) to Light (J4). Vary the intensity of light shining

on the light sensor located near the top left corner of the board. Notice what happens to the motor.

• Move the jumper to TEMP (J4). Blow on the temperature sensor located on the

top left corner of the board. Note what happens to the number displayed on the LCD.

• Move the jumper back to POT1. Move the jumper from N2 (J1) to D0 (J14). Watch

what happens to the intensity of LED D0 as you turn the potentiometer.

PICDEM™ Mechatronics

FIGURE 1-1: QUICK BOARD SETUP

PICDEMTM Mechatronics Demo Board User’s Guide

1.4 PICDEM™ MECHATRONICS DEVELOPMENT KIT CONTENTS

The PICDEM™ Mechatronics Development Kit contains the following items:

1. The PICDEM™ Mechatronics Printed Circuit Board (PCB) with motors

2. Pre-programmed PIC16F917 PICmicro

3. 10 wire jumpers

4. 8 2-pin shunts

5. CD-ROM including:

• PICDEM™ Mechatronics User’s Guide

• Workshop-in-a-Box presentation for training students on the board

(speaker notes included)

• Data sheets for the PIC16F91X, PIC16F631/677/685/687/689/690

and motors

• Application notes and other technical documentation

6. Sample kit including a PIC16F690 and PIC12F509 device

7. Microchip screwdriver

8. Registration Card

1.5 PICDEM™ MECHATRONICS LAYOUT

device

The PICDEM™ Mechatronics is shown in Figure 1-2. A PIC16F917 microcontroller is populated in the 40-pin socket, in which 22 out of the

36 available I/O pins are dedicated connections to several components on the board. The remaining 14 pins are available for the user to connect to the other components on the board, using the provided jumper wires. The dedicated connections connect to the following components:

• Switch 1 – 1 pin: MCLR

• LCD – 17 pins: VLCD1, VLCD2, VLCD3, COM0, COM1, COM2, COM3, SEG0,

SEG1, SEG2, SEG3, SEG6, SEG11, SEG16, SEG21, SEG22, SEG23

• In-Circuit Serial Programming™ Connector – ICSPDAT, ICSPCLK, MCLR

• RS-232 COM port – 2 pins: RX, TX

A 20-pin socket is provided and is compatible with 8/14/20-pin Flash-based microcontrollers. A PIC16F690 microcontroller is provided to use in the 20-pin socket, in which 5 out of the 18 available I/O pins are dedicated connections to several components on the board. The remaining 13 pins are available for the user to connect to the other components on the board using the provided jumper wires. The dedicated connections connect to the following components:

• Switch 1 – 1 pin: MCLR

• In-Circuit Serial Programming (ICSP™) Connector – ICSPDAT, ICSPCLK, MCLR

• RS-232 COM port: RX, TX

Note: Only one microcontroller should be loaded into the board at any given time.

Dedicated pins are indicated by a white box enclosing the pin designation next to each socket. Pay close attention to this designation, as the functionality of the dedicated pins are affected by the circuitry these pins are connected to. It is recommended that you use only the pins not designated as dedicated connections in your design.

The remaining components on the board must be connected to the microcontroller using the provided wire jumpers. The jumpers connect between the headers on either side of the microcontroller and the header pins next to the respective components on the board. The components on the board are labeled in Figure 1-2.

PICDEM™ Mechatronics

)

FIGURE 1-2: PICDEM MECHATRONICS DEMO BOARD HARDWARE

Legend:

6. RS-232 socket and associated

DC battery

hardware

7. Temperature sensor

8. Light sensor

9. 2 potentiometers

10. 32.768 kHz crystal

11. 4 tactile switches

12. In-Circuit Debugg er (ICD) co nne ctor13. In-Circuit Serial Programming™

(ICSP™) connector

Reset switch

associated MOSFET drivers and

logic

14. Over-current protection circuit with

15. 4 half-bridge MOSFET drives wit h

sense

speed of the Brushed DC motor

16. Current sense for output stage

17. Back Electromagnetic Force (EMF

18. Optical Interrupter for detecting the

19. Brushed DC motor

20. Stepper motor

21. Drive screw terminals

22. 9 V

power connections

1. 40-pin socket

2. 20-pin socket

3. On-board voltage regulator and

pins on the 40-pin socket

4. 8 LEDs

5. 39 segment LCD connected to 14

PICDEMTM Mechatronics Demo Board User’s Guide

The reasons for requiring you to use the provided jumpers to connect components to the microcontroller are three-fold.

1. Y ou will gain knowledge and experience by physically connecting components to the microcontroller.

2. There are more peripherals than pins on the microcontrollers so that you can do more with the board.

3. Should you choose to use the board to experiment on your own, the board allows you the flexibility to do so. You can try experimenting with peripherals not covered in the projects in Chapter 2. “Example Projects”.

1.6 REQUIRED TOOLS

One of the following programming tools is needed in order to complete the projects in the next chapter:

• PICkit™ 2 Microcontroller Programmer (Part# DV164120)

• MPLAB

Figures 1-3 and 1-4 illustrate how to connect each of these tools to the PICDEM Mechatron ics Demo Board.

ICD 2 In-Circuit Debugger/Programmer (Part# DV164007 includes a

DC power supply and serial cable)

1.7 PICDEM™ MECHATRONICS SETUP

Please take a moment to review the following steps, prior to using the board. These steps ensure the board is configured correctly before beginning the projects.

1.7.1 Jumper Settings

Remove all 2-pin shunts (jumpers), except for JP8. On JP8, the shunt should be connected in the right most position (indicated by the “+5V” label), which ensures that the drive stage is powered by +5 V

1.7.2 Board Power-Up

Supply power to the board in one of the following ways:

• Connect a 9-12 V

is grounded externally and positive internally.

• Connect a 9-12 V

terminals.

• Connect a 9 V

• Connect a 5 VDC (1.2 amp minimum) supply to TP2 or TP3.

When power is initially connected, the “PWR ON” LED should light up. The “FAULT” LED in the over-current sense circuit will also be on when the board is powered up. Clear the Fault by pressing SW5 (CLR FAULT) switch. The board is now properly configured for the projects.

DC (0.75 amp minimum) supply via J9. The connector’s polarity

DC (0.75 amp minimum) supply to the P21 and P20 screw

DC battery to the battery connector.

DC.

PICDEM™ Mechatronics

FIGURE 1-3: CONNECTING THE MPLAB ICD 2 TO THE PICDEM

MECHATRONICS DEMO BOARD

PICDEM™ Mechatronics

MICROCHIP

MPLAB

BUSY

ERROR

POWE

ICD 2

FIGURE 1-4: CONNECTING THE PICkit™ 2 TO THE PICDEM

MECHATRONICS DEMO BOARD

PICDEM™ Mechatronics

PICDEMTM Mechatronics Demo Board User’s Guide

1.8 GENERAL PICDEM™ MECHATRONICS DEMONSTRATION BOARD INFORMATION

Power Supply Maximum Ratings

Supply voltage: 12 VDC Output current (drive stage): 1.2A (total)

1.8.1 Experimentation

The PICDEM Mechatronics Demo Board was designed for your experimentation. After completing the projects in Chapter 2. “Example Projects”, please experiment freely on your own. Voltage power supplies and motors, other than those provided in the kit, may be used.

The driver portion of the board (the part that supplies power to the motors) has an over-current sense circuit and will trip should the motor draw more than 1.2 amps. The LM7805 regulator also protects the circuit by limiting the current consumed by the board. Logic has also been put in place to ensure that the P and N-Channel MOSFET s connected to each of the output drives can not be turned on simultaneously.

Note: Although reasonable measures have been taken to protect the board from

the occasional mistake, THE BOARD MA Y BE DAMAGED if proper design techniques are not used and special attention to the schematic is not made.

1.8.2 On-Board Status LEDs

There are eight status LEDs on the board specifically provided to assist the user in the developing and debugging of your code. The user can output register values on one of the Ports of the microcontroller and have a binary reading of the value of that register. Connect the LEDs as shown in Figure 1-5. For instance, if it is suspected that the STATUS register is not being set appropriately , move the STATUS value into PORTC. If PORTC is attached as shown in Figure 1-5, the LEDs will show the value of STATUS.

PICDEM™ Mechatronics

FIGURE 1-5: CONNECTING PORTC PINS TO LEDS FOR DEBUGGING

1.8.3 OVER-CURRENT PROTECTION CIRCUIT

The over-current protection circuit included on the board shuts down the drive portion of the circuit if the board drives 1.2 amps continually for 100 ms or longer. Upon powering up the board, the “FAULT” LED will be on. The drive circuit must be reset manually by pressing the CLEAR FAULT button in the lower right hand portion of the board every time the board is initially supplied with power. Otherwise, a Fault is present when the “FAUL T” LED is illuminated and must be manually reset by pressing the same button. If you use your own motor, keep current draw less than 1.2A, as the over-current protection circuit will not allow driving a motor at or above this rating.

1.8.4 MOTOR CONNECTION

The motors provided on the PICDEM Demo Board must be manually connected to the Drive screw terminals. The kit includes a Microchip screwdriver to facilitate in making these connections.

Note: The supplied Brushed DC motor and Bipolar Stepper motor are subject to

change as the motor manufacturers cannot guarantee the same model numbers will be available indefinitely. Please refer to Microchip’s web page (www.microchip.com) for the current data sheets for the motors supplied with this kit, if the motor supplied on your board differs from the motor data sheets found on the CD-ROM.

1.8.5 SERIAL COMMUNICATION

The JP2 jumper is normally not populated with a shunt. With no shunt present, the board is configured for serial communications via the PICmicro Connecting a shunt between the bottom two pins (TX and RX) allows the user to transmit and receive serial communication via one pin (jumper between the microcontroller and the TX/RX pin on JP2).

USART (or EUSAR T).

PICDEMTM Mechatronics Demo Board User’s Guide

1.8.6 SNAP-OFF SENSORS

The temperature sensor and light sensor can be snapped off to give greater flexibility in using these sensors. For example, the temperature sensor may be snapped off and moved into a more hostile environment, while keeping the board within sight. Once, snapped off, solder wires of the same length between the adjoining holes (i.e., JP3 and JP4 for the temperature sensor) on the PICDEM Mechatronics Demo Board and the sensor board.

1.8.7 BACK EMF SCALING RESISTORS

If choosing to drive your own Brushed DC motor with the PICDEM Mechatronics Demo Board at a voltage higher than +5 V of 0-5 V locations may be populated with resistors to create a simple voltage divider circuit. TP1 is the output of this voltage divider. See the schematic in Appendix A. “Hardware Schematics” for further clarification.

DC. Resistor locations, R55 and R56, are provided for this purpose. These

1.8.8 CURRENT SENSE

The output stage of the board incorporates a simple current sensing circuit, which is assessable at J15 (CURRENT SENSE). At this pin, the voltage is equal to current ± 10%. For instance, if a motor is being driven and it is drawing 0.9 amps, the voltage at the header is 0.9 volts (± 10%).

DC, the Back EMF must be scaled down into a range

PICDEM™ Mechatronics

1.8.9 HEADER/JUMPER FUNCTIONS

TABLE 1-1: HEADER/JUMPER FUNCTIONS

Header/

Jumper #

Output MOSFET drive pins.

Description

J2 Full-bridge drive circuit (Drives 1 and 2): Place three shunts vertically on

these pins to create a full-bridge drive circuit incorporating Drives 1 and 2.

J3 Full-bridge drive circuit (Drives 3 and 4): Place three shunts vertically on

these pins to create a full-bridge drive circuit incorporating Drives 3 and

Temperature sensor, light sensor, potentiometers, 32.768 oscillator and switches signal pins.

J5 J6

Right-side signal pins of the 20-pin DIP socket (U2, pins 11-20). Left-side signal pins of the 20-pin DIP socket (U2, pins 1-10).

J7* Optical interrupter feedback signal pins.

J10 J13

Right-side signal pins of the 40-pin DIP socket (U1, pins 21-40).

Left-side signal pins of the 40-pin DIP socket (U1, pins 1-20). J14 LED connect pins. J15 J16

Current sense feedback from the drive stage.

Back EMF feedback signal pins. JP2 Single-pin serial communication jumper (see Section 1.8.5 “Serial

Communication” for details). JP8 Drive circuit voltage selection. See diagram on board.

* On these jumpers, the pins are connected in pairs horizontally. This allows

one pin to be used for jumping to/from the microcontroller (using a wire jumper) and the other pin for probing the circuit with test equipment.

PICDEMTM Mechatronics Demo Board User’s Guide

NOTES:

2.1 INTRODUCTION

The following projects cover basic mechatronic principles such as reading a sensor, interfacing to a LCD and driving a motor. These projects also provide examples of how to use the various PICmicro sequentially so that you will build knowledge as you progress from one project to the next.

Those who are new to programming PIC to the comments in the source code for each of the projects. Though these projects are not intended to teach you the Microchip Assembly language, you will be able to get a good grasp of Microchip’s Assembly language by reading the source code.

Microchip has published application notes and other documents covering the applications in each of these projects. These documents can be found on the provided CD-ROM. Any updates to the applicable documents are available on Microchip’s web site. Please reference these documents while exploring each of the projects.

Note: See Section 1.7 “PICDEM™ Mechatronics Setup” for instructions on

PICDEMTM MECHATRONICS

DEMO BOARD USER’S GUIDE

Chapter 2. Example Projects

microcontroller per ipherals. The projects are presented

microcontrollers should pay special attention

how to setup the board to its “initial” condition prior to doing projects.

PICDEMTM Mechatronics Demo Board User’s Guide

2.2 LOADING PROJECTS IN MPLAB® IDE

The firmware for the projects is arranged in corresponding project folders in the install directory for the PICDEM Mechatronics CD. If you installed the CD in the default directory, the firmware for Project 1 is located in:

C:\PICDEM Mechatronics\firmware\Project1

Opening a Project

1. Start MPLAB IDE.

2. In the menu bar choose File -> Open Workspace.

3. Find the project folder.

4. Open the *.mcw file. The project window for Project 1 is shown in Figure 2-1.

FIGURE 2-1: PROJECT WINDOW

2.3 EXAMPLE PROJECTS

PIC16F917 Projects:

• Project 1 : Hello World (Light a LED)

• Project 2: Dusk Indicator Using the Voltage Comparator

• Project 3: Thermometer Using the Analog-to-Digital Converter

• Project 4: Digital Clock Using Timer1

• Project 5: Brushed DC Speed Control with Optical Encoder Feedback

• Project 6: Brushed DC Speed Control with Back EMF Feedback

• Project 7: Stepper Motor Control; Single Stepping, Half Stepping and Microstepping

• Project 8: PC Interface Using the USART

PIC16F690 Project:

• Project 9: Brushed DC Motor Control Using the ECCP

Example Projects

2.3.1 Project 1: Hello World (Light a LED)

When learning to use a new computer language, the first practical lesson traditionally instructs the user how to print “Hello World” on the screen. Staying with tradition, this project will make your PICDEM Mechatronics Demo Board say “Hello World” in the most practical way a microcontroller can – lighting a LED.

Objectives

1. Use the PIC16F917 to read a tactile switch input.

2. Implement switch debouncing.

3. Toggle a LED when a switch is pushed.

Applicable Technical Documents

PICkit 1™ Flash Starter Kit User’s Guide (DS40051): Exercise 2

Jumper Configuration

• RD7 (J10) to D0 (J14)

• RA0 (J13) to SW2 (J4)

FIGURE 2-2: PROJECT 1: JUMPER DIAGRAM

FIGURE 2-3: PROJECT 1: SCHEMATIC

1 kΩ

VDD

11/32

12/31

VDD

RA0

VSS

PIC16F917

RD7

R36 270 Ω

VDD

10 kΩ

SW2

PICDEMTM Mechatronics Demo Board User’s Guide

Instructions

Pressing SW2 toggles LED (D0) on and off.

Discussion

Switch debouncing is done to ensure that mechanical contact chatter in the switch is not mistaken for more than one button push. Debouncing also ensures that for every one press of the button, only one function is executed. In this project that function is toggling a LED.

Note: See Section 2.2 “Loading Projects in MPLAB

the source files for this project and all subsequent projects.

IDE” for the location of

Example Projects

2.3.2 Project 2: Dusk Indicator Using the Voltage Comparator

If you have yard lights or a porch light at home that automatically turns on at dusk then you are familiar with the application we will create in this project. The comparator on the PIC16F917 will be used to compare the voltage level from the potentiometer to the voltage level out from the light sensor. When the intensity of the light to the sensor is reduced below the trip point set by the potentiometer, the LED will turn on.

Objectives

1. Use the internal analog comparator module.

2. Implement software hysteresis to stabilize the comparator output.

Applicable Technical Documents

PICmicro® Comparator Tips ‘n Tricks (DS41215)

Jumper Configuration

• C1- (J13) to LIGHT (J4)

• C1+ (J13) to POT1 (J4)

• RD7 (J10) to D0 (J14)

FIGURE 2-4: PROJECT 2: JUMPER DIAGRAM

PICDEMTM Mechatronics Demo Board User’s Guide

FIGURE 2-5: PROJECT 2: SCHEMATIC

VDD

C1-

C1+

PIC16F917

RD7

VSS

12/31

R36

270 Ω

0.1

C24

μF

VDD

Light Sensor

VDD

VBAT

GND

TSL251RD

VDD

11/32

R31

1 kΩ

POT1

10 kΩ

R10 1 kΩ

Instructions

Provide a light source for the light sensor and set Potentiometer 1 to the desired trip point. Block the light source and LED1 should turn on. Experiment with the set point and the amount to which you block the light from the sensor. Move your hand slowly in front of the sensor and note that the LED does not flicker. This demonstrates how software hyster esis prev ents the ou tput of the comp arat or fr om ch atter ing n ear th e trip point.

Discussion

Comparators are found in many PIC microcontrollers due to the versatility and low cost they offer the user. As you can see, the comparator is one of the more easily used peripherals. Refer to the Comparator Tips ‘n Tricks pamphlet included on the CD in this kit for more information on comparators.

Example Projects

2.3.3 Project 3: Thermometer Using the Analog-to-Digital Converter

This project shows how to read an analog temperature sensor and display the temperature on a LCD. The Analog-to-Digital Converter module is used to read the analog voltage output from the temperature sensor. Then, the resulting value is converted into degrees Celsius and displayed.

Objectives

1. Use the Analog-to-Digital Converter module on the PIC16F917 to read the analog voltage output of the TC1047A temperature sensor.

2. Gain knowledge about the LCD module and using the LCD module worksheet.

Applicable Technical Documents

Precision Temperature-to-Voltage Converter (TC1047/A) Data Sheet (DS21498)

Jumper Configuration

• AN0 (J13) to TEMP (J4)

FIGURE 2-6: PROJECT 3: JUMPER DIAGRAM

FIGURE 2-7: PROJECT 3: SCHEMATIC

VDD

Temp.

Sensor

C24

0.1

μF

VDD

VSS

TC1047A

Out

R19

1 kΩ

11/32

C28

0.1 μF

12/31

VDD

AN0

PIC16F917

COMX

SEGX

LCD1

Common pins

Segment pins

VIM-332-DP

PICDEMTM Mechatronics Demo Board User’s Guide

Instructions

The LCD displays a temperature reading in degrees Celsius. Breathe on the temperature sensor or introduce another heat source. The displayed temperature should rise. Move the jumper wire from the temperature sensor to the potentiometer (POT1 on J4). Move the potentiometer to view the full range of temperature conversion.

Discussion

The project introduces you to use of the Analog-to-Digital Converter module. One of the biggest advantages to using a PICmicro require temperature sensing is that the microcontroller can be used to calibrate the temperature sensor reading automatically (over varying supply voltages and process variations in the parts themselves). This saves the manufacturer costly calibration time at the factory that is typically required by traditional temperature sensing technologies.

LCD functions were introduced in this project for displaying data on the provided LCD. Take a look at the LCD worksheet in Appendix B. “LCD Segment Mapping Worksheet”. This is the same worksheet located in the PIC16F91X Data Sheet (DS41250), only it has been filled in using the information from the PICDEM Mechatronics Schematic (see Appendix A. “Hardware Schematics” for the schematic). In the LCD source code provided in this project, you can see that the information in this worksheet has been converted into #define statements for each of the segments.

microcontroller in applications that

Example Projects

2.3.4 Project 4: Digital Clock Using Timer1

Most appliances that have a LCD show a clock readout when the appliance is not in use. In this project, Timer1 is used to create a real-time clock readout on the LCD.

Objectives

1. Configure the PIC16F917 to use the 32.768 kHz crystal to clock Timer1.

2. Convert Timer1 into seconds, minutes and hours.

Applicable Technical Documents

Clock Design Using Low Power/Cost Techniques Application Note, AN615 (DS00615)

Jumper Configuration

• T1OSI (J13) to OSI (J4) – See note.

• T1OSO (J13) to OSO (J4) – See note.

• RA3 (J13) to SW2 (J4)

• RA4 (J13) to SW3 (J4)

• RA5 (J13) to SW4 (J4)

FIGURE 2-8: PROJECT 4: JUMPER DIAGRAM

Note: Crystal circuits are very sensitive to noise and stray capacitances. In

general, the traces between a crystal and a microcontroller should be as short as possible. The reason the PICDEM Mechatronics Demo Board strayed from good design practice was to give you the option to use pins RA7 and RA6 for other functions.

PICDEMTM Mechatronics Demo Board User’s Guide

FIGURE 2-9: PROJECT 4: SCHEMATIC

VDD

11/32

LCD1

Common pins

Segment pins

VIM-332-DP

VDD

32.768 kHz

VDD

C35 22 pF

C34 22 pF

PIC16F917

COMX

T1OSI

SEGX

T1OSO

SW2

SW3

VDD

10 kΩ

R6 10 kΩ

1 kΩ

RA0

RA1

RA3

12/31

1 kΩ

10 kΩ

SW4

Instructions

Use Switch 2 to set the hours and Switch 3 to set the minutes. Pressing and holding either of these switches will make the hours or minutes increment at a fast rate. T oggle between displaying the time (hours and minutes) and displaying the seconds by pressing Switch 4.

Discussion

The 32.768 kHz crystal is used to take the guess work out of creating a clock display. Y ou may recognize this frequency as being 2 clock pulses to seconds in the binary world of a microcontroller. Every time bit 15 in Timer1 changes, one second has elapsed. A crystal is used because an RC oscillator will have an unacceptable degree of error after several days.

kHz. This make s it very ea sy to conv ert

Example Projects

2.3.5 Project 5: Brushed DC Motor Speed Control with Optical

Encoder Feedback

Motor control is required in many mechatronic applications ranging from power windows to washing machine cycle control. This project will demonstrate speed control of a Brushed DC motor. Brushed DC motor control is simple as the commutation, or sequencing of power to the various windings, is automatically performed by the motor’s brushes. In this project, the Capture Compare PWM (CCP) module will be used in PWM mode to generate a Brushed DC motor drive. Timer1 will measure speed feedback from the optical interrupter on the board. The optical interrupter circuit generates a high signal when light passes through the slots in the encoder disk. By measuring the time between pulses, the speed of the motor can be determined. A real-life application example includes precision speed control of a fan or hard disk drive.

Objectives

1. Configure the CCP module to generate a PWM signal.

2. Use a PWM signal to vary the speed of a Brushed DC motor.

3. Configure Timer1 to use the optical interrupter as its clock source.

Applicable Technical Documents

Brushed DC Motor Fundamentals Application Note, AN905 (DS00905) Low-Cost Bidirectional Brushed DC Motor Control Using the PIC16F684 Application

Note, AN893 (DS00893)

Jumper Configuration

• RD7 (J10) to P1 (J1)

• CCP2 (J10) to N2 (J1)

• AN0 (J13) to POT1 (J4)

• RC5 (J10) to Optical Interrupter (J7)

• Attach the motor leads to DRIVE1 (P9) and DRIVE2 (P10).

• J2 and J3 should be unpopulated (no shunts present).

• Connect the right and center pins of JP8 using a shunt.

PICDEMTM Mechatronics Demo Board User’s Guide

FIGURE 2-10: PROJECT 5: JUMPER DIAGRAM

OPTICAL

MOTOR

Brushed DC Lead

D DC

BRUSHE

INTERRUPTER

32.768 kHz

CRYSTAL

FIGURE 2-11: PROJECT 5: SCHEMATIC

Example Projects

POT1

10 kΩ

R20

470 Ω

D12

VDD

R10

1 kΩ

R11

20 kΩ

VDD

C26 1000 pF

R22

470 Ω

11/32

12/31

PIC16F917

VDD

AN0

RC5

COMX

SEGX

RD7

CCP2

LCD1

Common pins

Segment pins

VIM-332-DP

VDD

U11:B

10 kΩ

Motor

U10:A

10 kΩ

Simplified circuit shows equivalent functionality

Instructions

Use POT1 to adjust the speed of the motor. Turn the potentiometer counter-clockwise to reduce speed; turn it clockwise to increase motor speed. Multiply the LCD display by 1000 to obtain speed in RPM.

Discussion

With the CCP module operating with 8 bits of resolution, the module can output a PWM signal at a frequency of 31.2 kHz. This is sufficiently high frequency that motor whine is outside of the audible frequency for humans. This is especially important in applications where the motor may turn at slow speeds.

Using an optical sensor to gather feedback from a motor is an integral part of many mechatronic systems. Some systems require a constant speed over varying loads. An optical encoder is similar to the optical interrupter circuit used in this project. The difference is that an optical encoder uses more than one optical sensor (as many as four) to deduce speed and shaft position.

Note: The optical interrupter circuit is susceptible to interference from outside

infrared light sources (i.e., incandescent lights, sunlight, etc.). It may be necessary to cover the optical sensor to obtain an accurate reading.

PICDEMTM Mechatronics Demo Board User’s Guide

2.3.6 Project 6: Brushed DC Speed Control with Back EMF Feedback

Project 5 uses an optical encoder to provide motor speed feedback. In this project, another fo rm of spe ed meas urement will be explor ed, Back El ectrom otive Fo rce (Bac k EMF). Y ou may be aware that a Brushed DC motor, when turned by hand, will produce voltage at its leads, becoming a generator. When a Brushed DC motor is being driven, and then the drive voltage is removed for a brief amount of time, the voltage generated by the inertia of the motor will be proportional to its speed. This voltage is the Back EMF.

Objectives

1. Effectively read Back EMF using the on-board Analog-to-Digital Converter.

2. Interpret the Back EMF into a speed for the motor.

Applicable Technical Documents

Low-Cost Bidirectional Brushed DC Motor Control Using the PIC16F684 Application Note, AN893 (DS00893)

Jumper Configuration

• RD7 (J10) to P1 (J1)

• CCP2 (J10) to N2 (J1)

• AN0 (J13) to POT1 (J4)

• AN1 (J13) to BACK EMF (J16)

• Attach the motor leads to DRIVE1 (P9) and DRIVE2 (P10).

• J2 and J3 should be unpopulated.

• Connect the right and center pins of JP8 using a shunt.

Example Projects

FIGURE 2-12: PROJECT 6: JUMPER DIAGRAM

Brushed DC Lead

PICDEMTM Mechatronics Demo Board User’s Guide

FIGURE 2-13: PROJECT 6: SCHEMATIC

VDD

POT1

10 kΩ

Back EMF

R10

1 kΩ

R32

1 kΩ

VDD

11/32

C26 1000 pF

C36 1000 pF

12/31

AN0

AN4

PIC16F917

COMX

SEGX

RD7

CCP2

Common pins

Segment pins

LCD1

VIM-332-DP

10 kΩ

VDD

U11:B

Back EMF

Motor

U10:A

Simplified circuit shows

equivalent functionality

Instructions

POT1 adjusts the speed of the motor. Set POT1 at 100% to run the motor at full speed. The speed indicated on the LCD should be similar to the speed shown in Project 5. Next, run the motor at half speed by setting POT1 to 50% and do the comparison again.

Note: Different motors have different speed characteristics. The motor used at the

time this manual was written may be different from the motor shipped with your PICDEM Mechatronics Demo Board. Verify that the motor data sheet included on the CD-ROM matches the motor on the board. If they are different, go to Microchip’s web site for updates to this project.

Discussion

Back EMF is typically not as accurate as speed feedback from an optical encoder. However, in many applications the accuracy does not have to be very precise and measuring Back EMF is more cost effective than any other speed feedback mechanism.

Example Projects

2.3.7 Project 7: Stepper Motor Control : Single Stepping, Half

Stepping and Microstepping

This project demonstrates the various ways to drive a bipolar stepper motor. There are several ways to step a stepper motor, the most basic of which is single stepping, or moving the motor in one-step increments. If a motor is specified as a 7.5 degrees-per-step motor, then single stepping the motor will result in moving the shaft of the motor 7.5 degrees per step. Half stepping the same motor would result in a 3.75 degrees step.

Torque and current are linearly related for a stepper motor. Therefore, if two sinusoidal currents are applied to the windings, offset by a 90 degree phase shift relative to one another, then the stepper motor will have constant torque as it turns. This results in a very smooth rotation of the shaft. Applying current to the windings in this way is referred to as sine-cosine microstepping.

Objectives

1. Single-step a stepping motor.

2. Half-step the motor.

3. Micro-step the motor.

Applicable Technical Documents

Stepping Motor Fundamentals Application Note, AN907 (DS00907) Stepper Motor Control Using the PIC16F684 Application Note, AN906 (DS00906)

Jumper Configuration

• AN0 (J13) to POT1 (J4)

• RA4 (J13) to SW2 (J4)

• RD7 (J10) to P1 (J1)

• RD6 (J10) to P2 (J1)

• RD5 (J10) to P3 (J1)

• RD4 (J10) to P4 (J1)

• CCP1 (J10) to PWM1 (J1)

• CCP2 (J10) to PWM3 (J1)

• Place three shunts (two pin jumpers) vertically on J2 where it is labeled “Connect

for Full-Bridge”.

• Place three shunts (two pin jumpers) vertically on J3 where it is labeled “Connect

for Full-Bridge”.

• Connect the BROWN lead of the stepper motor to Drive 1 (P9).

• Connect the ORANGE lead of the stepper motor to Drive 2 (P10).

• Connect the RED lead of the stepper motor to Drive 3 (P12).

• Connect the YELLOW lead of the stepper motor to Drive 4 (P11).

• Connect the right and center pins of JP8 using a shunt.

PICDEMTM Mechatronics Demo Board User’s Guide

FIGURE 2-14: PROJECT 7: JUMPER DIAGRAM

Brown

Orange

Red

Yellow

FIGURE 2-15: PROJECT 7: SCHEMATIC

Example Projects

VDD

RD7

Stepper

Winding 1

5 kΩ

VDD

Br Or

VDD

5 kΩ

VDD

5 kΩ

RD6

CCP1

Stepper

Winding 2

5 kΩ

RD5

RD4

VDD

5 kΩ

CCP2

PIC16F917

VDD

11/32

RA1

1 kΩ

10 kΩ

SW2

VDD

R10

POT1

AN0

C26

1000 pF

1 kΩ

10 kΩ

12/31

* = These are simplified circuits that show the equivalent functionality.

PICDEMTM Mechatronics Demo Board User’s Guide

Instructions

Adjusting POT1 varies the speed of the motor. Toggle between single stepping, half stepping, and microstepping modes by pressing SW2. At low speeds, the motor should noticeably step in single stepping and half stepping modes. The movement will be quite jerky in both modes, though to a lesser extent in the half stepping mode. In microstepping mode, the jerky motion should be virtually eliminated.

Discussion

Stepper motors are used in many positioning applications. For example, ink jet printers and smaller CNC machines employ stepper motors. Stepper motors are ideal for these applications because, as long as they are not overloaded, the distance a stepper motor moves is always known. Stepper motors are also brushless, which makes them more reliable than brushed motors. Finally, stepper motors are very responsive to starting and stopping and will produce the highest torque at low speeds.

Half stepping is used to give a stepping motor two times its rated step resolution. However, there is a word of caution. A stepper motor is typically not rated to have more than one winding energized at a time. As a result, the motor will heat up if both windings are energized at the rated voltage of the motor. To offset this, when both windings are energized simultaneously , the average current to each winding should be 0.707 times the rated current.

Microstepping offers several advantages over single stepping and half stepping. First, torque is fairly constant between steps. This results in smoother rotation and decreased shaft oscillation. Secondly, a higher step resolution is achieved. This means a low-cost motor can be used in an application that would normally require a more expensive, higher resolution motor. Finally, the current in the motor windings is being controlled in a way that prevents the motor from running outside its rated current, thereby eliminating the excess heat associated with half stepping. The drawback to microstepping is that the drive circuitry is more complex.

Example Projects

2.3.8 Project 8: PC Interface Using the USART

Communicating with the serial port on a PC is a very useful tool. Applications include a piece of test equipment that needs to interface to a PC or a design that uses the serial port during development to configure the device. In this project, the PIC16F917 will use the USART to receive commands from a PC application. Another notable feature to this project is that the firmware implements an auto-baud routine to sync up with the application.

Objectives

1. Use the provided PIC® MCU Communicator GUI to manipulate the I/O on the PIC16F917.

2. Understand what an auto-baud routine entails.

Applicable Technical Documents

Asynchronous Communications with the PICmicro® USART Application Note, AN774 (DS00774)

Jumper Configuration

• Make sure there are no jumpers or shunts on JP2.

• RD7 (J10) to D0 (J14)

• Connect a serial cable between the board and PC

FIGURE 2-16: PROJECT 8: JUMPER DIAGRAM

PICDEMTM Mechatronics Demo Board User’s Guide

FIGURE 2-17: PROJECT 8: SCHEMATIC

VDD

11/32

R60

300 Ω

R61

300 Ω

12/31

VDD

PIC16F917

RD7

R36

270 Ω

J19

6 7 8 9

DE9S-FRS

U18

C21

C20

0.1 μF

89 6

MAX3232CUE

C17 C17

1 2 3 4 5

C17

VCC V+

1 3 4

5 11

10 12

GNDV-

Instructions

Locate the PIC® MCU Communicator GUI in the PIC MCU Communicator folder in Project 8 on the CD-ROM. Choose the Comm Port and baud rate. Then click “Open Comm.” Enter “TRISD” in the top Label text field. Enter “088” into the top Addr text field. Check the top Hex box. Enter “7F” into the Data field. In the box labeled “Bit Control” enter “PORTD” in the label text field. Enter “008” in the Addr field. Finally, toggle bit 7 using the “T” button under that bit. The LED on your board should toggle on and off. See Figure 2-18.

FIGURE 2-18: PIC

MCU COMMUNICATOR INTERFACE

Example Projects

Discussion

The firmware for this project implements RS-232 communication between the PC and PIC16F917. The USART is used to perform this communication. If a crystal oscillator were used as the clock source for the PIC16F917, auto-baud would not be necessary. However, because the PIC16F917 is using the internal RC oscillator, it is necessary to perform auto-baud. Auto-baud refers to sending out a known character from the PC, the MCU measures the time it takes to receive the character, interprets this time into bit width, and then sets up the baud rate registers accordingly for the USART . This method allows the RS-232 communication to be free from errors on different microcontrollers and over temperature variations.

The PIC MCU Communicator GUI is included in this project as an example GUI. However, it is also a great tool for debugging. Experiment with using the GUI to setup other peripherals on the microcontroller.

PICDEMTM Mechatronics Demo Board User’s Guide

2.3.9 Project 9: Brushed DC Motor Control Using the ECCP

This project is very similar to Project 5, only in this project, we are using the Enhanced Capture Compare PWM (ECCP) module in the PIC16F690 (see note). In PWM mode, the ECCP module has four outputs for directly driving an H-bridge circuit. This makes implementing bidirectional speed control of a Brushed DC motor a simple task.

Note: T o change microcontrollers, disconnect power from the board. Remove the

PIC16F917 microcontroller from U1 and install the PIC16F690 in U2. Reconnect power to the board.

Objectives

1. Configure the ECCP module for Full-Bridge mode.

2. Change motor directions.

Applicable Technical Documents

Low-Cost Bidirectional Brushed DC Motor Control Using the PIC16F684 Application Note, AN893 (DS00893)

Jumper Configuration

• P1A (J6) to P1 (J1)

• P1B (J6) to N1 (J1)

• P1C (J6) to P2 (J1)

• P1D (J5) to N2 (J1)

• AN2 (J5) to POT1 (J4)

• RA5 (J6) to SW2 (J4)

• Make sure there are no shunts (two pin jumpers) on J2.

• Attach the Brushed DC motor leads to DRIVE1 (P9) and DRIVE2 (P10).

• Connect the right and center pins of JP8 using a shunt.

Example Projects

FIGURE 2-19: PROJECT 9: JUMPER DIAGRAM

Brushed DC Lead

PICDEMTM Mechatronics Demo Board User’s Guide

FIGURE 2-20: PROJECT 9: SCHEMATIC

+5V

10 kΩ

P1A

PIC16F690

Motor

10 kΩ

P1B

RA5

10 kΩ

P1C

AN2

10 kΩ

P1D

+5V

VDD

10 kΩ

SW2

C26

1000 pF

1 kΩ

* = These are simplified circuits that show the equivalent functionality.

R10

1 kΩ

VDD

POT1

10 kΩ

Example Projects

Instructions

Use POT1 to adjust the speed of the motor. SW2 toggles between the following four modes of operation:

•Motor Off

•Forward

•Motor Off

• Reverse

Discussion

The ECCP module is ideal for driving a full-bridge circuit. Dead-band Delay Control and Automatic Shutdown are some of the other features of the ECCP module when configured in PWM mode. Dead-band Delay Control allows you to control when the MOSFET s in the full-bridge circuit are turned on and off, in relation to one another. This is done in order to automatically account for the MOSFET turn-on and turn-off times. Automatic Shutdown allows you to define the shutdown state of the ECCP when a shutdown event occurs.

PICDEMTM Mechatronics Demo Board User’s Guide

NOTES:

Chapter 3. Troubleshooting

3.1 INTRODUCTION

This chapter describes common problems associated with using the PICDEM™ Mechatronics and steps on how to resolve them.

3.2 COMMON PROBLEMS

3.2.1 VDD Is Below 5V

The board must be powered by one of the following:

• A 9-12 V

•A 9V

•A 5V

Supplying less than 9 V to function properly causing V

DC source at the screw terminals (P20 and P21)

DC source at J9 DC battery DC power source at TP2 and TP3

PICDEMTM MECHATRONICS

DEMO BOARD USER’S GUIDE

DC at J9 or the screw terminals will not allow the regulator (U3)

DD to be below 5 VDC.

3.2.2 No Voltage On Drive Stage

There must be a two-pin shunt present on JP8 connecting the middle pin to +5 VDC or 9-12 V

DC. This is the supply reference for the drive stage. If the FAUL T LED (D8) is on,

the drive stage is disabled. Press the CLR FAULT button (SW5) to enable the drive stage.

3.2.3 FAULT LED Stays On Or Continues To Trip When SW5 Is Pressed

Verify that the motor is not drawing over 1.2 amps. Check the voltage at CURRENT SENSE (J15) before the FAULT LED turns on again. Voltage is equal to the current at J15, therefore, if the voltage is 1.2V or greater, the drive is drawing too much current or possibly shorted.

Verify the motor is being driven properly. The N-channel and P-channel MOSFETs on any given Drive (DRIVE 1, DRIVE 2, etc.) should not be turned on simultaneously . (See note).

J2 connects the MOSFET control lines for DRIVE 1 and DRIVE 2 and J3 connects the control lines for DRIVE 3 and DRIVE 4. If shunts are present on J2 and J3, verify that they are connected intentionally and not from a previous design.

Note: Hardware is in place to ensure the N-channel and P-channel MOSFETs on

a given Drive are not turned on at the same time. However, if you are switching the N-channel MOSFET rapidly, it is possible for both MOSFETs to be on at the same time.

PICDEMTM Mechatronics Demo Board User’s Guide

3.2.4 Microcontroller Does Not Run After Programming By The MPLAB ICD 2

When using the MPLAB ICD 2 as a programmer, the microcontroller will not run unless you disconnect the MPLAB ICD 2 or release the MPLAB ICD 2 from Reset. Figure 3-1 shows the “Release From Reset” button.

FIGURE 3-1: RELEASE FROM RESET BUTTON

3.2.5 Back EMF At J16 Is Floating

Check that a Fault has not occurred by checking that the FAULT LED is off. Verify the Brushed DC motor is connected between DRIVE 1 and DRIVE 2. In order to measure Back EMF, DRIVE 1 must float and DRIVE 2 must be grounded (i.e., the N-channel MOSFET for Drive 2 is the only MOSFET turned on).

3.2.6 Board Is Non-Functional When Microcontrollers Are In st alled In Both U1 And U2

Only one microcontroller should be installed on the board at any given time.

3.2.7 Optical Interrupter Is Not Providing The Expected Feedback

The optical interrupter circuit is susceptible to interference from outside infrared light sources (i.e., incandescent lights, sunlight, etc.). It may be necessary to block this source or turn off the light source when using the optical interrupter.

3.2.8 Serial Communication Does Not Appear To Be Working

If using the USART on the PIC16F690 or PIC16F917, note that the TX and RX pins are already connected. Make sure there is no shunt present on JP2.

Appendix A. Hardware Schematics

A.1 INTRODUCTION

This appendix contains the PICDEM™ Mechatronics Board Schematic Diagram.

FIGURE A-1: SCHEMATIC DIAGRAM (PAGE 1 OF 7)

PICDEMTM MECHATRONICS

DEMO BOARD USER’S GUIDE

PICDEMTM Mechatronics Demo Board User’s Guide

FIGURE A-2: SCHEMATIC DIAGRAM (PAGE 2 OF 7)

Hardware Schematics

FIGURE A-3: SCHEMATIC DIAGRAM (PAGE 3 OF 7)

PICDEMTM Mechatronics Demo Board User’s Guide

FIGURE A-4: SCHEMATIC DIAGRAM (PAGE 4 OF 7)

101112131415

C1-

C2-

C1+

C2+

V+

VCC

GND

V-

8 9

Hardware Schematics

FIGURE A-5: SCHEMATIC DIAGRAM (PAGE 5 OF 7)

5, 6

7, 8

5, 6

7, 8

PICDEMTM Mechatronics Demo Board User’s Guide

FIGURE A-6: SCHEMATIC DIAGRAM (PAGE 6 OF 7)

5, 6

7, 8

5, 6

7, 8

Hardware Schematics

FIGURE A-7: SCHEMATIC DIAGRAM (PAGE 7 OF 7)

PICDEMTM Mechatronics Demo Board User’s Guide

NOTES:

Appendix B. LCD Segment Mapping Worksheet

B.1 INTRODUCTION

This appendix contains the LCD Segment Mapping Worksheet.

PICDEMTM MECHATRONICS

DEMO BOARD USER’S GUIDE

LCD Segment Mapping Worksheet

APPENDIX B: LCD SEGMENT MAPPING WORKSHEET

Functions

28/40-pin

LCD

LCDDATAx

LCD

/SDO

Segment

Address

Segment

REF+

LCDDATAx

LCD

LCDDATAx

LCD

COM0 COM1 COM2 COM3 Pin No. PORT Alternate

LCDDATAx

LCD

Function

Address

Segment

Address

Segment

Address

SEG6 LCDDATA0, 6 2A LCDDATA 3, 6 2F LC DDATA6, 6 2E LCDDATA9, 6 2D 14/18 RC3

SEG7 LCDDATA0, 7 LCDDATA3, 7 LCDDATA6, 7 LCDDATA9, 7 3/3 RA1 AN1

SEG8 LCDDATA1, 0 LCDDATA4, 0 LCDDATA7, 0 LCDDATA10, 0 18/26 RC7 RX/DT/SDI/SDA

SEG9 LCDDATA1, 1 LCDDATA4, 1 LCDDATA7, 1 LCDDATA10, 1 17/25 RC6 TX/CK/SCK/SCL

SEG10 LCDDATA1, 2 LCDDATA4, 2 LCDDATA7, 2 LCDDATA 10, 2 16/24 RC5 T1CKI/CCP1

SEG0 LCDDATA0, 0 A LCDDATA 3, 0 V LCDDATA6, 0 K LCDDATA9, 0 Ω 21/33 RB0 INT

SEG11 LCDDATA1, 3 3B LCDDATA 4, 3 3G LCDDATA7, 3 3C LCDDATA10, 3 3DP 15/23 RC4 T1G

SEG12 LCDDATA1, 4 LCDDATA4, 4 LCDDATA7, 4 LCDDATA 10, 4 2/2 RA0 AN0

SEG13 LCDDATA1, 5 LCDDATA4, 5 LCDDATA7, 5 LCDDATA 10, 5 28/40 RB7 ICSPDAT/ICDDAT

SEG1 LCDDATA0, 1 RC LCDDATA3, 1 BATT LCDDATA 6, 1 - LCDDATA9, 1 AC 22/34 RB1

SEG2 LCDDATA0, 2 DH LCDDATA3, 2 RH LCDDATA6, 2 B-C LCDDATA9, 2 4DP 23/35 RB2

SEG3 LCDDATA0, 3 3A LCDDATA 3, 3 3F LC DDATA6, 3 3E LCDDATA9, 3 3D 24/36 RB3

SEG4 LCDDATA0, 4 LCDDATA3, 4 LCDDATA6, 4 LCDDATA9, 4 6/6 RA4 C1OUT/T0CKI

SEG5 LCDDATA0, 5 LCDDATA3, 5 LCDDATA6, 5 LCDDATA9, 5 7/7 RA5 C2OUT/AN4/SS

SEG14 LCDDATA1, 6 LCDDATA4, 6 LCDDATA7, 6 LCDDATA 10, 6 27/39 RB6 ICSPCK/ICDCK

SEG16 LCDDATA2, 0 S1 LCDDATA 5, 0 S2 LCDDATA8, 0 m LCDDATA11, 0 M -/26 RD3

SEG17 LCDDATA2, 1 LCDDATA5, 1 LCDDATA8, 1 LCDDATA11, 1 -/27 RD4

SEG18 LCDDATA2, 2 LCDDATA5, 2 LCDDATA8, 2 LCDDATA11, 2 -/28 RD5

SEG19 LCDDATA2, 3 LCDDATA5, 3 LCDDATA8, 3 LCDDATA11, 3 -/29 RD6

SEG20 LCDDATA2, 4 LCDDATA5, 4 LCDDATA8, 4 LCDDATA11, 4 -/30 RD7

SEG21 LCDDATA2, 5 2B LCDDATA 5, 5 2G LCDDATA8, 5 2C LCDDATA11, 5 2DP -/8 RE0 AN5

SEG22 LCDDATA2, 6 1A LCDDATA 5, 6 1F LC DDATA8, 6 1E LCDDATA11, 6 1D -/9 RE1 AN6

SEG15 LCDDATA1, 7 LCDDATA4, 7 LCDDATA7, 7 LCDDATA 10, 7 5/5 RA3 AN3/V

SEG23 LCDDATA2, 7 1B LCDDATA5, 7 1G LCDDATA8, 7 1C LCDDATA11, 7 -/10 RE2 AN7

NOTES:

LCD Segment Mapping Worksheet

WORLDWIDE SALES AND SERVICE

AMERICAS

Corporate Office

2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 480-792-7200 Fax: 480-792-7277 Techn ical Su pport: http://support.microchip.com Web Address: www.microchip.com

Atlanta

Alpharetta, GA Tel: 770-640-0034 Fax: 770-640-0307

Boston

Westborough, MA Tel: 774-760-0087 Fax: 774-760-0088

Chicago

Itasca, IL Tel: 630-285-0071 Fax: 630-285-0075

Dallas

Addison, TX Tel: 972-818-7423 Fax: 972-818-2924

Detroit

Farmington Hills, MI Tel: 248-538-2250 Fax: 248-538-2260

Kokomo

Kokomo, IN Tel: 765-864-8360 Fax: 765-864-8387

Los Angeles

Mission Viejo, CA Tel: 949-462-9523 Fax: 949-462-9608

Santa Clara

Santa Clara, CA Tel: 408-961-6444 Fax: 408-961-6445

Toronto

Mississauga, Ontario, Canada Tel: 905-673-0699 Fax: 905-673-6509

ASIA/PACIFIC

Asia Pacific Office

Suites 3707-14, 37th Floor Tower 6, The Gateway Habour City, Kowloon Hong Kong Tel: 852-2401-1200 Fax: 852-2401-3431

Australia - Sydney

Tel: 61-2-9868-67 33 Fax: 61-2-9868-6755

China - Beijing

Tel: 86-10-8528-2 100 Fax: 86-10-8528-2104

China - Chengdu

Tel: 86-28-8665-5 511 Fax: 86-28-8665-7889

China - Fuzhou

Tel: 86-591-8750-3506 Fax: 86-591-8750-3521

China - Hong Kong SAR

Tel: 852-2401-1200 Fax: 852-2401-3431

China - Qingdao

Tel: 86-532-8502-7355 Fax: 86-532-8502-7205

China - Shanghai

Tel: 86-21-5407-5 533 Fax: 86-21-5407-5066

China - Shenyang

Tel: 86-24-2334-2 829 Fax: 86-24-2334-2393

China - Shenzhen

Tel: 86-755-8203-2660 Fax: 86-755-8203-1760

China - Shunde

Tel: 86-757-2839-5507 Fax: 86-757-2839-5571

China - Wuhan

Tel: 86-27-5980-5 300 Fax: 86-27-5980-5118

China - Xian

Tel: 86-29-8833-7 250 Fax: 86-29-8833-7256

ASIA/PACIFIC

India - Bangalore

Tel: 91-80-4182-8400 Fax: 91-80-4182-8422

India - New Delhi

Tel: 91-11-4160-8631 Fax: 91-11-4160-8632

India - Pune

Tel: 91-20-2566-1512 Fax: 91-20-2566-1513

Japan - Yokohama

Tel: 81-45-471- 6166 Fax: 81-45-471-6122

Korea - Gumi

Tel: 82-54-473-4301 Fax: 82-54-473-4302

Korea - Seoul

Tel: 82-2-554-7200 Fax: 82-2-558-5932 or 82-2-558-5934

Malaysia - Penang

Tel: 60-4-646-8870 Fax: 60-4-646-5086

Philippines - Manila

Tel: 63-2-634-9065 Fax: 63-2-634-9069

Singapore

Tel: 65-6334-8870 Fax: 65-6334-8850

Taiwan - Hsin Chu

Tel: 886-3-572-9526 Fax: 886-3-572-6459

Taiwan - Kaohsiung

Tel: 886-7-536-4818 Fax: 886-7-536-4803

Taiwan - Taipei

Tel: 886-2-2500-6610 Fax: 886-2-2508-0102

Thailand - Bangkok

Tel: 66-2-694-1351 Fax: 66-2-694-1350

EUROPE

Austria - Wels

Tel: 43-7242-2244-3910 Fax: 43-7242-2244-393

Denmark - Copenhagen

Tel: 45-4450-2828 Fax: 45-4485-2829

France - Paris

Tel: 33-1-69-53 -63-20 Fax: 33-1-69-30-90-79

Germany - Munich

Tel: 49-89-627-144-0 Fax: 49-89-627-144-44

Italy - Milan

Tel: 39-0331-742611 Fax: 39-0331-466781

Netherlands - Drunen

Tel: 31-416-690399 Fax: 31-416-690340

Spain - Madrid

Tel: 34-91-708-08-90 Fax: 34-91-708-08-91

UK - Wokingham

Tel: 44-118-921-5869 Fax: 44-118-921-5820

08/29/06

Microchip Technology PICDEM™ Mechatronics Demonstration Board User’s Guide

Specifications and Main Features

Frequently Asked Questions

User Manual

Preface

1.1 INTRODUCTION

1.2 HIGHLIGHTS

1.3 QUICK START GUIDE

1. Attach the leads of the Brushed DC motor to Drive 1 and Drive 2 using the screwdriver.

2. Connect POT1 (on J4) to C1- (on J13) using a wire jumper.

3. Connect P1 (on J1) to RD7 (on J10) using a wire jumper.

4. Connect N2 (on J1) to RD2 (on J10) using a wire jumper.

5. Connect the right and center pins on JP8 using a shunt.

FIGURE 1-1: QUICK BOARD SETUP

1.4 PICDEM™ MECHATRONICS DEVELOPMENT KIT CONTENTS

1. The PICDEM™ Mechatronics Printed Circuit Board (PCB) with motors

3. 10 wire jumpers

4. 8 2-pin shunts

5. CD-ROM including:

6. Sample kit including a PIC16F690 and PIC12F509 device

7. Microchip screwdriver

8. Registration Card

1.5 PICDEM™ MECHATRONICS LAYOUT

FIGURE 1-2: PICDEM MECHATRONICS DEMO BOARD HARDWARE

7. Temperature sensor

8. Light sensor

9. 2 potentiometers

11. 4 tactile switches

16. Current sense for output stage

19. Brushed DC motor

20. Stepper motor

21. Drive screw terminals

1. 40-pin socket

2. 20-pin socket

4. 8 LEDs

1.6 REQUIRED TOOLS

1.7 PICDEM™ MECHATRONICS SETUP

1.7.1 Jumper Settings

1.7.2 Board Power-Up

1.8 GENERAL PICDEM™ MECHATRONICS DEMONSTRATION BOARD INFORMATION

1.8.1 Experimentation

1.8.2 On-Board Status LEDs

FIGURE 1-5: CONNECTING PORTC PINS TO LEDS FOR DEBUGGING

1.8.3 OVER-CURRENT PROTECTION CIRCUIT

1.8.4 MOTOR CONNECTION

1.8.5 SERIAL COMMUNICATION

1.8.6 SNAP-OFF SENSORS

1.8.7 BACK EMF SCALING RESISTORS

1.8.8 CURRENT SENSE

1.8.9 HEADER/JUMPER FUNCTIONS

2.1 INTRODUCTION

2.2 LOADING PROJECTS IN MPLAB® IDE

1. Start MPLAB IDE.

2. In the menu bar choose File -> Open Workspace.

3. Find the project folder.

4. Open the *.mcw file. The project window for Project 1 is shown in Figure 2-1.

FIGURE 2-1: PROJECT WINDOW

2.3 EXAMPLE PROJECTS

2.3.1 Project 1: Hello World (Light a LED)

1. Use the PIC16F917 to read a tactile switch input.

2. Implement switch debouncing.

3. Toggle a LED when a switch is pushed.

FIGURE 2-2: PROJECT 1: JUMPER DIAGRAM

FIGURE 2-3: PROJECT 1: SCHEMATIC

2.3.2 Project 2: Dusk Indicator Using the Voltage Comparator

1. Use the internal analog comparator module.

2. Implement software hysteresis to stabilize the comparator output.

FIGURE 2-4: PROJECT 2: JUMPER DIAGRAM

FIGURE 2-5: PROJECT 2: SCHEMATIC

2.3.3 Project 3: Thermometer Using the Analog-to-Digital Converter

2. Gain knowledge about the LCD module and using the LCD module worksheet.

FIGURE 2-6: PROJECT 3: JUMPER DIAGRAM

FIGURE 2-7: PROJECT 3: SCHEMATIC

2.3.4 Project 4: Digital Clock Using Timer1

2. Convert Timer1 into seconds, minutes and hours.

FIGURE 2-8: PROJECT 4: JUMPER DIAGRAM

FIGURE 2-9: PROJECT 4: SCHEMATIC

1. Configure the CCP module to generate a PWM signal.

2. Use a PWM signal to vary the speed of a Brushed DC motor.

3. Configure Timer1 to use the optical interrupter as its clock source.